From MCD at goshenarc.org Sat Apr 1 00:15:26 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 19:15:26 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010018 SWOMCD SPC MCD 010017 OHZ000-KYZ000-INZ000-010145- MESOSCALE DISCUSSION 0381 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CST FRI MAR 31 2006 AREAS AFFECTED...SERN LOWER MI...ERN THROUGH SRN IND AND WRN OH CONCERNING...TORNADO WATCH 117...118... VALID 010017Z - 010145Z THREAT FOR LARGE HAIL...ISOLATED STRONG WIND GUSTS AND ISOLATED TORNADOES PERSISTS ACROSS THE REMAINING PORTIONS OF WW 117 AND 118. STORMS WILL APPROACH THE ERN PORTION OF THE WATCHES BY 01Z. WW MAY BE NEEDED SOON FOR PARTS OF EXTREME SERN IND INTO WRN OH. EARLY THIS EVENING A SQUALL LINE EXTENDS FROM SERN LOWER MI SWWD THROUGH NWRN OH INTO CNTRL AND SWRN IND. THE LINE IS MOVING EAST AT AROUND 30 KT. STORMS ARE CURRENTLY MOVING THROUGH THE AXIS OF BEST INSTABILITY WITH MLCAPE FROM 500 TO 1000 J/KG. OBJECTIVE ANALYSIS INDICATES INSTABILITY IS MORE MARGINAL AND THE BOUNDARY LAYER MORE STABLE WITH EWD EXTENT INTO OH WHERE LESS HEATING OCCURRED TODAY. THIS COULD SERVE AS A LIMITING FACTOR AS STORMS MOVE EWD. HOWEVER...THETA-E ADVECTION ALONG THE STRONG SWLY LOW LEVEL JET MAY CONTRIBUTE TO SOME NEWD DESTABILIZATION INTO WRN OH THIS EVENING. VERTICAL SHEAR PROFILES WILL REMAIN SUFFICIENT TO SUPPORT ORGANIZED STORMS GIVEN SUFFICIENT DESTABILIZATION. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CLE...ILN...LMK...IWX...IND... 40708307 39118448 38918541 40138487 41638348 WWWW From MCD at goshenarc.org Sat Apr 1 01:28:21 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 20:28:21 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010131 SWOMCD SPC MCD 010130 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-010300- MESOSCALE DISCUSSION 0382 NWS STORM PREDICTION CENTER NORMAN OK 0730 PM CST FRI MAR 31 2006 AREAS AFFECTED...FAR ERN AR INTO TN AND NRN MS/AL/NWRN GA CONCERNING...TORNADO WATCH 119... VALID 010130Z - 010300Z SCATTERED THUNDERSTORMS...SOME SEVERE...WILL PERSIST FOR A COUPLE MORE HOURS...BUT AN ADDITIONAL WW IS NOT EXPECTED DUE TO DECREASING THREAT WITH TIME. SWLY FETCH OF RELATIVELY WARM/MOIST AIR CONTINUES TO FEED STORMS WITHIN WARM ADVECTION ZONE. AREA VAD WIND PROFILES AND PROFILER DATA INDICATE FAVORABLE HODOGRAPHS FOR SUPERCELLS...WITH MODERATELY STRONG LOW LEVEL SHEAR ESPECIALLY INTO MIDDLE TN. WITH TIME...LOW LEVEL JET WILL VEER AS UPPER SYSTEM SHIFTS NEWD...WHICH WILL DECREASE SHEAR PROFILES AND ALLOW FOR CONTINUED WARMING ALOFT. THIS...COMBINED WITH CESSATION OF SURFACE HEATING...WILL CAUSE A GRADUAL DECREASE IN STORM INTENSITY TO BELOW SEVERE LIMITS BY THE TIME WW 119 EXPIRES. THE THREAT HAS ALREADY ENDED OVER NWRN PORTIONS OF THE WATCH. ADDITIONAL DEVELOPMENT...MOST LIKELY SUB-SEVERE...IS EXPECTED ACROSS NRN MS AND AL WITHIN INSTABILITY AXIS. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN...LZK... 33399093 33639147 35659092 36258819 36518609 36498474 35388473 34098487 33508579 WWWW From MCD at goshenarc.org Sat Apr 1 02:27:54 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 21:27:54 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010227 SWOMCD SPC MCD 010226 INZ000-KYZ000-010330- MESOSCALE DISCUSSION 0383 NWS STORM PREDICTION CENTER NORMAN OK 0826 PM CST FRI MAR 31 2006 AREAS AFFECTED...SRN IND THROUGH NRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 118... VALID 010226Z - 010330Z TORNADO WATCH 118 WILL LIKELY BE ALLOWED TO EXPIRE AT 03Z. SEVERE THREAT MAY PERSIST A COUPLE HOURS BEYOND 03Z FOR A FEW COUNTIES IN SRN IND AND NRN KY...BUT A GRADUAL WEAKENING TREND IS EXPECTED LATER THIS EVENING. SQUALL LINE EXTENDS FROM WRN KY INTO SRN IND. THE LINE IS MOVING SEWD AT AROUND 20 KT. TREND HAS BEEN FOR STRONGER STORMS TO PERSIST ON THE SRN END OF THE LINE ACROSS SRN IND IN CLOSER PROXIMITY TO FEED OF HIGHER INSTABILITY WITH SBCAPE NEAR 1000 J/KG. VERTICAL SHEAR PROFILES WILL CONTINUE TO SUPPORT ORGANIZED STORM STRUCTURES WITHIN THE LINE. HOWEVER...AS THE BOUNDARY LAYER CONTINUES TO COOL AND THE LOW LEVEL FLOW VEERS...STORMS SHOULD BEGIN TO UNDERGO A GRADUAL DECREASE AFTER ANOTHER COUPLE HOURS. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...PAH... 38538505 37918583 37668708 38298729 38588627 38888527 WWWW From MCD at goshenarc.org Sat Apr 1 03:39:55 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 22:39:55 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010339 SWOMCD SPC MCD 010338 OHZ000-KYZ000-INZ000-010445- MESOSCALE DISCUSSION 0384 NWS STORM PREDICTION CENTER NORMAN OK 0938 PM CST FRI MAR 31 2006 AREAS AFFECTED...NRN KY...SWRN OH THROUGH EXTREME SERN IND CONCERNING...SEVERE THUNDERSTORM WATCH 120... VALID 010338Z - 010445Z SEVERE THREAT MAY PERSIST FOR ANOTHER 30 MIN IN REMAINING PORTION OF WW 120. BEYOND THIS TIME...ANY REMAINING SEVERE THREAT WILL LIKELY HAVE SHIFTED S OF WW 120 INTO PORTIONS OF EXTREME NRN KY BY 04Z. SQUALL LINE EXTENDS FROM SWRN OH SWWD THROUGH EXTREME NRN KY INTO SRN IND. THE LINE IS MOVING SEWD AT AROUND 20-25 KT. STRONGEST PORTION OF THE LINE CONTINUES TO PERSIST ALONG THE SWRN FLANKS IN PROXIMITY TO FEED OF BETTER INSTABILITY...WHILE STORMS ON THE NRN END WEAKEN WITH EWD EXTENT. OVERALL TREND SHOULD CONTINUE TO BE FOR STORMS TO GRADUALLY WEAKEN AS THE BOUNDARY LAYER STABILIZES AND THE LOW LEVEL FLOW VEERS. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK... 38688449 38958531 39368357 WWWW From MCD at goshenarc.org Sat Apr 1 04:22:14 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 23:22:14 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010421 SWOMCD SPC MCD 010421 TXZ000-010545- MESOSCALE DISCUSSION 0385 NWS STORM PREDICTION CENTER NORMAN OK 1021 PM CST FRI MAR 31 2006 AREAS AFFECTED...WRN THROUGH NWRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 010421Z - 010545Z STRONGER STORMS DEVELOPING OVER NWRN TX MAY BE CAPABLE OF PRODUCING HAIL. CURRENT THINKING IS THAT COVERAGE WILL PROBABLY NOT BE SUFFICIENT TO WARRANT A WW AT THIS TIME...BUT TRENDS WILL CONTINUE TO BE MONITORED. LATE THIS EVENING A WARM FRONT EXTENDS FROM SERN OK SWWD THROUGH NWRN TX. WRN PORTION OF THIS BOUNDARY HAS BEGUN TO LIFT NWD DUE TO AN INCREASE IN SLY LOW LEVEL JET OF 25 TO 30 KT ASSOCIATED WITH DEVELOPING LEE TROUGH. THE WARM SECTOR S OF THE WARM FRONT IS MODERATELY UNSTABLE...AND THIS HIGHER THETA-E AIR WILL CONTINUE TO BE ADVECTED NWD OVERNIGHT. A FEW ELEVATED STORMS HAVE DEVELOPED OVER WRN TX JUST S OF LUBBOCK WITHIN ZONE OF ISENTROPIC ASCENT N OF THE WARM FRONT ASSOCIATED WITH THE MODEST LOW LEVEL JET. THE UPPER PATTERN IS CHARACTERIZED BY A BROAD UPPER LEVEL RIDGE WITH RELATIVELY WEAK FLOW ALOFT RESULTING IN VERTICAL SHEAR PROFILES SUPPORTIVE PRIMARILY OF MULTICELL CONVECTION. HOWEVER...STEEP MID LEVEL LAPSE RATES AND MODERATE MUCAPE SUGGEST A FEW UPDRAFTS MAY BE STRONG ENOUGH TO SUPPORT A THREAT FOR HAIL. LOW LEVEL JET IS RATHER BROAD AND IS FORECAST TO VEER WITH TIME. THIS SUGGESTS ADDITIONAL DEVELOPMENT FARTHER NE INTO NWRN TX MAY BE POSSIBLE. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 32620088 32420187 33590143 34129886 33619829 WWWW From MCD at goshenarc.org Sat Apr 1 07:08:33 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 02:08:33 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010708 SWOMCD SPC MCD 010707 OKZ000-TXZ000-010930- MESOSCALE DISCUSSION 0386 NWS STORM PREDICTION CENTER NORMAN OK 0107 AM CST SAT APR 01 2006 AREAS AFFECTED...WRN N TX AND SWRN-SCNTRL OK CONCERNING...CONVECTIVE TRENDS VALID 010707Z - 010930Z TSTMS WITH MARGINALLY SEVERE HAIL WILL SPREAD ENEWD FROM WRN N TX INTO SWRN/SCNTRL OK THROUGH 12Z. WW IS NOT EXPECTED. EARLY MORNING SFC ANALYSIS PLACES A FRONT FROM SERN OK SWWD INTO THE TX S PLAINS. SLY 30-40 KT LLJ CONTINUES TO IMPINGE ON THIS BOUNDARY AND IS SUPPORTING ELEVATED MULTI-CELL TSTM CLUSTER OVER WRN N TX. AS THE LLJ VEERS THIS MORNING...TSTMS ARE APT TO MOVE/DEVELOP FARTHER N/NE ACROSS SWRN/SCNTRL OK THROUGH DAYBREAK. CLOUD-BEARING SHEAR IS NOT PARTICULARLY STRONG OWING TO CLOSE PROXIMITY OF THE UPPER RIDGE AXIS. BUT...PARCELS FEEDING THE TSTMS WILL BE EMANATING FROM STEEP LAPSE RATES...RESULTING IN STRONG TO MARGINALLY SEVERE PULSE-TYPE STORMS WITH HAIL. GIVEN THE MAGNITUDE OF DRY AIR BETWEEN THE NEAR-SFC INVERSION AND CLOUD BASE...GUSTY WINDS MAY OCCUR WITH THE STORMS AS WELL. GIVEN THE MARGINALITY OF HAIL SIZE AND SPATIAL COVERAGE...A WW IS NOT ANTICIPATED. ..RACY.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB... 34510051 34979900 35129706 34989644 34539623 33879634 33459757 33329861 33249961 33610007 WWWW From MCD at goshenarc.org Sat Apr 1 11:40:21 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 06:40:21 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011139 SWOMCD SPC MCD 011139 VTZ000-MAZ000-NYZ000-PAZ000-011415- MESOSCALE DISCUSSION 0387 NWS STORM PREDICTION CENTER NORMAN OK 0539 AM CST SAT APR 01 2006 AREAS AFFECTED...EXTREME NERN PA...CNTRL/ERN NY AND WRN NEW ENGLAND CONCERNING...CONVECTIVE TRENDS VALID 011139Z - 011415Z A LINE OF CONVECTION WILL PRODUCE GUSTY WINDS /ISOLD DAMAGING WINDS/ AND PERHAPS SMALL HAIL AS IT MOVES ACROSS EXTREME NERN PA...CNTRL/ERN NY AND WRN NEW ENGLAND THROUGH LATE MORNING. WW IS NOT EXPECTED. LEADING EDGE OF STRONG LARGE SCALE ASCENT ASSOCIATED WITH THE UPPER LEVEL LOW WAS SPREADING EWD ACROSS THE LWR GRTLKS REGION AT DAYBREAK PER WATER VAPOR IMAGERY. ASSOCIATED COLD FRONT HAS BECOME ACTIVE SINCE 09Z WITH A FORCED LINE OF LOW-TOPPED CONVECTION ACROSS WRN NY AND NCNTRL PA. THIS LINE SHOULD BE MAINTAINED AS IT TRANSLATES ENEWD AT 30-35 KTS INTO CNTRL/ERN NY AND NERN PA BETWEEN 13-16Z AND INTO WRN NEW ENGLAND BY EARLY AFTN. INSTABILITY AHEAD OF THE LINE WILL BE MARGINAL...THOUGH A NARROW TONGUE OF 50-55F DEW POINTS WILL LIKELY BE IN PLACE JUST AHEAD OF THE LINE. ANY POCKETS OF BOUNDARY LAYER HEATING WILL BOOST BUOYANCY AND THE FRONTAL CIRCULATION...CONTRIBUTING TO BRIEF STRONGER UPDRAFTS. MOREOVER...LARGELY UNIDIRECTIONAL WSWLY FLOW REGIME AOA 30-40 KTS JUST ABOVE THE SFC COULD CAUSE LOCAL OUTFLOW ACCELERATIONS/SMALL SCALE BOWS TO DEVELOP WITH ATTENDANT ISOLD DAMAGING WINDS...PRIMARILY LATER THIS MORNING. OTHERWISE...SMALL HAIL MAY OCCUR WITH THE STRONGER UPDRAFTS. ..RACY.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BTV...ALY...BGM...BUF... 42117709 43277633 44137580 45067388 44687313 43957298 43017311 42287329 41947381 41627555 WWWW From MCD at goshenarc.org Sat Apr 1 16:07:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 11:07:48 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011607 SWOMCD SPC MCD 011606 ARZ000-TXZ000-OKZ000-011800- MESOSCALE DISCUSSION 0388 NWS STORM PREDICTION CENTER NORMAN OK 1006 AM CST SAT APR 01 2006 AREAS AFFECTED...ERN OK...WRN AR...NE TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011606Z - 011800Z A WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A MORE ORGANIZED SEVERE THREAT. A STRONGER RETURN FLOW OF GULF MOISTURE THROUGH THE SOUTHERN/ EASTERN PLAINS IS BECOMING JUXTAPOSED WITH ZONE OF STRONGER LOW/MID LEVEL WARM ADVECTION IN WAKE OF LARGE NORTHEASTERN STATES UPPER TROUGH...AND AHEAD OF LARGE TROUGH PROGRESSING INTO THE INTERMOUNTAIN WEST. THIS APPEARS TO BE PROVIDING SUPPORT FOR RECENT CONVECTIVE DEVELOPMENT ACROSS NORTHEASTERN OKLAHOMA...WITH ADDITIONAL ACTIVITY POSSIBLE AS INHIBITION WEAKENS INTO EARLY AFTERNOON THROUGH A RATHER BROAD AREA OF EASTERN TEXAS/OKLAHOMA INTO THE LOWER MISSISSIPPI VALLEY. THOUGH...IN GENERAL...FLOW FIELDS ARE RELATIVELY WEAK...SHEAR SEEMS SUFFICIENT FOR AT LEAST BRIEF UPDRAFT ROTATION IN STRONGER CELLS DEVELOPING IN ENVIRONMENT WITH CAPE ON THE ORDER OF 1000 J/KG. ISOLATED MARGINALLY SEVERE HAIL APPEARS MOST LIKELY THREAT WITH INITIAL STORMS...AND THIS THREAT COULD INCREASE AS ACTIVITY BECOMES INCREASING SURFACE BASED THIS AFTERNOON. GIVEN PRESENCE OF DRY MID-LEVEL ENVIRONMENT...CONTINUED HEATING OF THE BOUNDARY LAYER WILL ALSO CONTRIBUTE TO AN INCREASING RISK OF ISOLATED DOWNBURSTS BY PEAK HEATING. MOST CONVECTION LIKELY WILL REMAIN RATHER UNORGANIZED. HOWEVER... FORCING ASSOCIATED WITH SUBTROPICAL IMPULSE PROGRESSING THROUGH BROADER SCALE RIDGE COULD AID THE EVOLUTION OF A LARGE CONVECTIVE CLUSTER IN CONFLUENT LOW-LEVEL FLOW REGIME...FROM PARTS OF EASTERN OKLAHOMA ACROSS CENTRAL/SOUTHERN ARKANSAS BY 21Z. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 35789620 36249569 36019416 35659271 35399165 34739115 33979121 33249281 33259393 33629499 33889552 34679610 34869614 WWWW From MCD at goshenarc.org Sat Apr 1 16:35:09 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 11:35:09 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011634 SWOMCD SPC MCD 011633 NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-NCZ000-011830- MESOSCALE DISCUSSION 0389 NWS STORM PREDICTION CENTER NORMAN OK 1033 AM CST SAT APR 01 2006 AREAS AFFECTED...SE VA THRU THE DELMARVA PEN INTO SRN NJ CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011633Z - 011830Z NEED FOR A WW IS NOT ANTICIPATED AT THE MOMENT DUE TO ANTICIPATED MARGINAL/LOCALIZED NATURE OF SEVERE THREAT...BUT TRENDS ARE BEING MONITORED. PRE-FRONTAL LOW-LEVEL THERMAL RIDGE AXIS EXTENDS EAST OF THE SOUTHERN APPALACHIANS THROUGH NORTHERN/MID ATLANTIC COASTAL AREAS. THIS FEATURE WILL BECOME THE FOCUS FOR STRONGEST DESTABILIZATION ...AND CONVECTIVE DEVELOPMENT...AS MID-LEVEL THERMAL TROUGH AXIS OVERSPREADS REGION THIS AFTERNOON. THIS SEEMS LIKELY TO COMMENCE BY 18Z...MOSTLY SOUTH/EAST OF THE WASHINGTON D.C. AREA...WITH ACTIVITY GRADUALLY INCREASING IN COVERAGE ACROSS SOUTHEAST VIRGINIA...THE DELMARVA PENINSULA...POSSIBLY THROUGH NEW JERSEY BY 21Z. IN GENERAL...MOISTURE LEVELS APPEAR MARGINAL FOR VIGOROUS UPDRAFTS...BUT STRONGER SURFACE HEATING ACROSS PARTS OF SOUTHEAST VIRGINIA AND THE SOUTHERN DELMARVA COULD COMPENSATE SOMEWHAT... CONTRIBUTING TO MIXED LAYER CAPE LOCALLY AS HIGH AS 1000 J/KG BY PEAK HEATING. IN MODERATE TO STRONGLY SHEARED AND COOL CYCLONIC FLOW REGION...THIS WILL CONTRIBUTE TO POTENTIAL FOR ISOLATED SEVERE STORMS...WITH LARGE HAIL/DAMAGING WIND GUSTS. OTHER STORMS FARTHER NORTH COULD ALSO APPROACH OR BRIEFLY EXCEED SEVERE CRITERIA. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...LWX...RAH... 36507587 36307670 36547813 36947830 37597767 38147706 38797655 39437597 39937521 40367449 40417419 40317376 WWWW From MCD at goshenarc.org Sat Apr 1 18:13:40 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 13:13:40 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011812 SWOMCD SPC MCD 011812 KSZ000-OKZ000-TXZ000-COZ000-011945- MESOSCALE DISCUSSION 0390 NWS STORM PREDICTION CENTER NORMAN OK 1212 PM CST SAT APR 01 2006 AREAS AFFECTED...PARTS OF SE CO/WRN KS SOUTHWARD THRU FAR WRN OK AND MUCH OF THE TX PNHDL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011812Z - 011945Z SEVERE THREAT IS EXPECTED TO INCREASE BY 03/21Z...WITH INCREASING TORNADIC POTENTIAL BY 02/00Z. A TORNADO WATCH MAY BECOME NECESSARY BY 20Z. UNCERTAINTIES CONCERNING CONVECTIVE DEVELOPMENT ARE STILL CONSIDERABLE. BUT...IT SEEMS MOST PROBABLE THAT FORCING ASSOCIATED WITH SHEARING IMPULSE COULD SUPPORT CONVECTIVE INITIATION IN BROKEN LINE ACROSS THE TEXAS/OKLAHOMA PANHANDLE REGION...AS IT LIFTS OUT OF BROADER SCALE WESTERN TROUGH INTO CENTRAL U.S.. RIDGE. DRY LINE IS EXPECTED TO SHARPEN NEAR THE ELKHART/AMARILLO/LUBBOCK AREAS BY PEAK HEATING...PROVIDING FOCUS FOR CONVECTIVE DEVELOPMENT...WHICH SHOULD QUICKLY BECOME SEVERE IN STRONGLY SHEARED...CONVECTIVELY UNSTABLE ENVIRONMENT. MIXED LAYER CAPE IS EXPECTED TO INCREASE IN EXCESS OF 2000 J/KG ALONG/EAST OF DRY LINE...CONTRIBUTING TO INTENSE UPDRAFTS. ALTHOUGH A LINE OF CONVECTION COULD EVOLVE SHORTLY AFTER INITIATION...SUPERCELLS ALSO APPEAR LIKELY WITHIN AND AHEAD OF LINE. CONVECTION WILL DEVELOP NORTHEASTWARD TOWARD THE DODGE CITY...GAGE AND CHILDRESS/ALTUS AREAS BETWEEN 21-00Z... ENCOUNTERING INCREASING MOIST BOUNDARY LAYER. AS THIS OCCURS...AND MID/UPPER JET STREAK BEGINS TO NOSE OUT OF THE SOUTHERN ROCKIES...ACCOMPANIED BY DEEPENING SURFACE LOW ACROSS EAST CENTRAL/SOUTHEAST COLORADO...HODOGRAPHS/THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASINGLY FAVORABLE FOR TORNADOES BY EARLY EVENING. ISOLATED LONG-LIVED SUPERCELLS ARE POSSIBLE...WITH ATTENDANT RISK FOR VERY LARGE HAIL AND POTENTIAL FOR STRONG TORNADOES. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...DDC...GLD...LUB...AMA...PUB... 35880221 36740221 38070159 38750044 38349942 37459977 36139957 34969937 34269984 33390101 33000228 33580244 34250235 35000200 WWWW From MCD at goshenarc.org Sat Apr 1 20:22:44 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 15:22:44 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012022 SWOMCD SPC MCD 012021 TXZ000-012145- MESOSCALE DISCUSSION 0391 NWS STORM PREDICTION CENTER NORMAN OK 0221 PM CST SAT APR 01 2006 AREAS AFFECTED...WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 012021Z - 012145Z WE ARE MONITORING THE DRYLINE SOUTH OF LBB FOR DEVELOPMENT. AN ADDITIONAL WW MAY BE REQUIRED NEXT HOUR OR SO. AIR MASS CONTINUES TO DESTABILIZE E OF DRYLINE WITH TEMPERATURES RISING INTO THE LOWER 80S. MODIFIED 18Z MIDLAND SOUNDING YIELDS STRONG INSTABILITY USING LOWER 60S DEWPOINT WITH LITTLE INHIBITION. ALTHOUGH CONVECTIVE INHIBITION IS STRONG FARTHER E AS SEEN ON OUN AND FWD SOUNDINGS...APPROACHING TROUGH WILL CONTINUE TO COOL TEMPERATURES WITHIN CAPPING LAYER AND REDUCE CIN. GIVEN A FEW MORE HOURS OF HEATING...AND INCREASING CONVERGENCE ALONG DRYLINE...AT LEAST ISOLATED DEVELOPMENT APPEARS LIKELY. EXISTING SHEAR PROFILES AT 20Z ALREADY FAVOR SUPERCELLS AND WILL ONLY INCREASE WITH TIME AS LOW LEVEL JET STRENGTHENS. THUS...VERY LARGE HAIL AND TORNADOES WILL BE POSSIBLE ESPECIALLY OVER NRN PARTS OF DISCUSSION AREA. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 33820150 33799906 32549891 31869885 31660123 32350131 33190139 WWWW From MCD at goshenarc.org Sat Apr 1 21:17:38 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 16:17:38 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012117 SWOMCD SPC MCD 012116 NEZ000-KSZ000-012245- MESOSCALE DISCUSSION 0392 NWS STORM PREDICTION CENTER NORMAN OK 0316 PM CST SAT APR 01 2006 AREAS AFFECTED...NW KS INTO SW NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 012116Z - 012245Z AN ADDITIONAL WW WILL LIKELY BE NEEDED WITHIN NEXT HOUR OR TWO. SURFACE LOW OVER EAST CENTRAL COLORADO IS SLOWLY DEEPENING...AND FORECAST TO CONTINUE TO DO SO INTO THE EARLY EVENING HOURS... PERHAPS SHIFTING TOWARD THE GOODLAND AREA BY 02-03Z. THIS WILL OCCUR AS INITIAL SHEARING IMPULSE LIFTS OUT OF THE SOUTHERN ROCKIES TOWARD CREST OF BROADER SCALE RIDGING OVER THE PLAINS/MISSISSIPPI VALLEY REGION. IN RESPONSE TO STRONGER SURFACE PRESSURE FALLS AND STRENGTHENING SOUTHEASTERLY FLOW TO THE EAST/NORTHEAST OF LOW...BOUNDARY LAYER IS IN PROCESS OF RAPIDLY DESTABILIZING ACROSS WESTERN KANSAS. SIMILAR DESTABILIZATION IS EXPECTED INTO AREAS SOUTH/EAST OF NORTH PLATTE NEB BY AROUND 00Z. THIS IS EXPECTED TO SUPPORT INCREASING POTENTIAL FOR STRONG/SEVERE THUNDERSTORM ACTIVITY. DEVELOPMENT IS ALREADY UNDERWAY ALONG DRY LINE FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE...AND NEW DEVELOPMENT APPEARS LIKELY THROUGH WARM SECTOR TO THE NORTH/EAST...BENEATH INCREASINGLY DIVERGENT UPPER FLOW. THIS IS EXPECTED BY 00Z...WITH FURTHER INCREASE EAST OF GOODLAND AND NORTH PLATTE INTO THE HILL CITY/GRAND ISLAND AREAS THROUGH 03Z. SHEAR PROFILES IN EXIT REGION OF APPROACHING MID-LEVEL JET STREAK WILL BE SUPPORTIVE OF SUPERCELLS IN ENVIRONMENT WITH CAPE RANGING FROM 1000 TO 2000 J/KG. VERY LARGE HAIL/DAMAGING WINDS AND ISOLATED TORNADOES ARE ALL LIKELY. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ICT...GID...LBF...DDC...GLD... 38460149 39060152 40330121 40970032 41179889 40969832 40199797 39309868 38699929 38490010 WWWW From MCD at goshenarc.org Sat Apr 1 22:10:27 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 17:10:27 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012209 SWOMCD SPC MCD 012208 OKZ000-KSZ000-TXZ000-020015- MESOSCALE DISCUSSION 0393 NWS STORM PREDICTION CENTER NORMAN OK 0408 PM CST SAT APR 01 2006 AREAS AFFECTED...SWRN KS / WRN OK / ERN TX PANHANDLE AND NW TX CONCERNING...TORNADO WATCH 121... VALID 012208Z - 020015Z THREAT FOR TORNADOES WILL INCREASE OVER THE NEXT FEW HOURS...WITH THE POTENTIAL FOR VERY LARGE DAMAGING HAIL AS WELL. STORMS CONTINUE TO DEVELOP E OF DRYLINE WHERE ENVIRONMENT HAS BECOME VERY UNSTABLE. SEVERAL CLUSTERS WERE NOTED ACROSS THE REGION...OVER SWRN KS...NEAR BGD AND SW OF CDS AT 22Z. MORE DEVELOPMENT IS LIKELY OVER FAR WRN OK WHERE TCU ARE RAPIDLY DEVELOPING. AREA PROFILERS INDICATE STRENGTHENING WIND FIELDS ALOFT WITH 50+ KT MID LEVEL FLOW ABOVE 3 KM ACROSS W TX. LOW LEVEL JET/850 FLOW IS ALSO INCREASING AND WILL PROVIDE AN INCREASINGLY FAVORABLE ENVIRONMENT FOR LONG LIVED SUPERCELLS. THUS...STORM STRUCTURE SHOULD BECOME MORE ORGANIZED WITH TIME...WITH THREAT OF TORNADOES INCREASING WITH LOW LEVEL SHEAR. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...DDC...LUB...AMA... 33779854 33780127 38190145 38199848 WWWW From MCD at goshenarc.org Sat Apr 1 23:38:12 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 18:38:12 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012337 SWOMCD SPC MCD 012337 KSZ000-OKZ000-020100- MESOSCALE DISCUSSION 0394 NWS STORM PREDICTION CENTER NORMAN OK 0537 PM CST SAT APR 01 2006 AREAS AFFECTED...MUCH OF OK INTO CENTRAL KS CONCERNING...TORNADO WATCH 121...123... VALID 012337Z - 020100Z ...TORNADO WATCH WILL BE REQUIRED DOWNSTREAM ACROSS MUCH OF CENTRAL KS INTO SRN OK... MULTIPLE SUPERCELL CLUSTERS ARE EVOLVING ACROSS WRN KS...SWD INTO NWRN TX. THIS ACTIVITY WILL CONTINUE TO EVOLVE AS IT SPREADS DOWNSTREAM INTO CENTRAL PORTIONS OF KS AND OK OVER THE NEXT FEW HOURS. LATEST MODEL GUIDANCE STRONGLY SUGGESTS LLJ WILL INCREASE SIGNIFICANTLY OVER THE NEXT 3 HOURS ALONG I-35 CORRIDOR. THIS WILL AID LOW LEVEL SHEAR AND STORM INFLOW FOR MAINTAINING SUPERCELL STRUCTURES EAST OF CURRENT WATCHES. TORNADO WATCH WILL BE ISSUED FOR THIS REGION BY 01Z. ..DARROW.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...TOP...ICT...OUN...DDC... 34329854 38179837 38989733 38189608 34419658 WWWW From MCD at goshenarc.org Sun Apr 2 00:31:34 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 19:31:34 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020030 SWOMCD SPC MCD 020030 ARZ000-OKZ000-020200- MESOSCALE DISCUSSION 0395 NWS STORM PREDICTION CENTER NORMAN OK 0630 PM CST SAT APR 01 2006 AREAS AFFECTED...AR CONCERNING...SEVERE THUNDERSTORM WATCH 122... VALID 020030Z - 020200Z ...LARGE HAIL MAY STILL ACCOMPANY STRONGER STORMS... WARM ADVECTION ALONG RETREATING WARM FRONT WILL CONTINUE TO AID NWD CONVECTIVE DEVELOPMENT ACROSS CNTRL/NRN AR THIS EVENING. WITH LOSS OF DAYTIME HEATING...IT APPEARS INSTABILITY WILL GRADUALLY WANE LESSENING SEVERE POTENTIAL WITH THIS NWD PROPAGATION. GIVEN DYNAMIC PROCESSES ARE BECOMING MORE FOCUSED ACROSS CNTRL OK INTO KS...LARGE SCALE PROCESSES WILL NOT PROVE TOO SUPPORTIVE FOR SUSTAINING ORGANIZED SEVERE ACROSS THIS REGION AFTER DARK. NOT ADDITIONAL WATCHES ARE ANTICIPATED AT THIS TIME. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...TSA... 33729237 34549423 36209493 36029262 34299111 WWWW From MCD at goshenarc.org Sun Apr 2 01:39:31 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 20:39:31 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020138 SWOMCD SPC MCD 020138 NEZ000-KSZ000-020315- MESOSCALE DISCUSSION 0396 NWS STORM PREDICTION CENTER NORMAN OK 0738 PM CST SAT APR 01 2006 AREAS AFFECTED...SERN NEB...NERN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020138Z - 020315Z ...SEVERE THREAT IS INCREASING ACROSS SERN NEB AND NERN KS. SEVERE THUNDERSTORM WATCH WILL BE ISSUED SOON... SQUALL LINE WITH EMBEDDED SUPERCELL STRUCTURES IS BECOMING A BIT MORE ORGANIZED AS IT LIFTS NEWD ACROSS CNTRL KS THIS EVENING. IT APPEARS THIS ACTIVITY WILL PROGRESS EAST AND NORTH OF CURRENT TORNADO WATCHES INTO A SLOWLY DESTABILIZING AIRMASS CAPABLE OF MAINTAINING DAMAGING WINDS AND LARGE HAIL THREAT. STRENGTH OF UPPER SHORTWAVE/ENHANCED LIFT SUGGEST SQUALL LINE WILL NOT DECREASE SIGNIFICANTLY IN INTENSITY OVER THE NEXT FEW HOURS. SEVERE THUNDERSTORM WATCH WILL LIKELY BE ISSUED SOON. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...TOP...GID... 38689709 40089786 40439930 41319826 40489613 38379551 WWWW From MCD at goshenarc.org Sun Apr 2 01:53:50 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 20:53:50 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020153 SWOMCD SPC MCD 020153 TXZ000-020330- MESOSCALE DISCUSSION 0397 NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CST SAT APR 01 2006 AREAS AFFECTED...SWRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020153Z - 020330Z ...SEVERE THUNDERSTORM WATCH MAY BE REQUIRED FOR PORTIONS OF SWRN/CNTRL TX... CONVECTION HAS RAPIDLY INCREASED OVER SWRN TX ALONG DRY LINE FROM ERN PECOS COUNTY INTO REAGAN COUNTY. DRT SOUNDING AT 00Z WAS NOT TERRIBLY CAPPED WITH WEAK MID LEVEL CAA NOTED AROUND 700MB. IT APPEARS SRN END OF PLAINS SHORTWAVE TROUGH WILL EJECT ACROSS PORTIONS OF CNTRL TX AIDING THIS CONVECTION IN THE SHORT TERM. ALTHOUGH FWD SOUNDING EXHIBITED QUITE A BIT MORE INHIBITION...SHEAR PROFILES SEEM FAVORABLE FOR SUSTAINING SQUALL LINE STRUCTURE AS IT SPREADS ACROSS THE EDWARDS PLATEAU OVER THE NEXT SEVERAL HOURS. SEVERE THUNDERSTORM WATCH MAY BE REQUIRED IF TRENDS CONTINUE. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SJT...MAF... 30700178 31520103 32200013 31669901 30630096 WWWW From MCD at goshenarc.org Sun Apr 2 02:18:32 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 21:18:32 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020217 SWOMCD SPC MCD 020217 OKZ000-TXZ000-020345- MESOSCALE DISCUSSION 0398 NWS STORM PREDICTION CENTER NORMAN OK 0817 PM CST SAT APR 01 2006 AREAS AFFECTED...CENTRAL OK CONCERNING...TORNADO WATCH 124... VALID 020217Z - 020345Z ...TORNADO THREAT APPEARS TO BE DECREASING ACROSS OK... SQUALL LINE HAS ORGANIZED ACROSS WRN OK AND IS SURGING ENEWD AT ROUGHLY 35KT. SUPERCELL STRUCTURES HAVE GRADUALLY DECREASED IN INTENSITY ALONG THIS LINE AND HAVE BECOME ILL DEFINED AS CELL MERGERS HAVE EVOLVED INTO BOW-LIKE STRUCTURES. IT APPEARS THE GREATEST RISK OF SEVERE OVER THE NEXT FEW HOURS WILL BE LARGE HAIL...ALONG WITH THE THREAT OF STRONG WINDS...ESPECIALLY AHEAD OF BOW-TYPE FEATURES. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...OUN... 36699636 34939684 34059792 34239894 34989825 36719788 WWWW From MCD at goshenarc.org Sun Apr 2 06:44:59 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 01:44:59 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020644 SWOMCD SPC MCD 020644 MOZ000-ARZ000-OKZ000-KSZ000-020845- MESOSCALE DISCUSSION 0399 NWS STORM PREDICTION CENTER NORMAN OK 1244 AM CST SUN APR 02 2006 AREAS AFFECTED...EXTREME ERN KS...WRN/CNTRL MO...ECNTRL OK AND NWRN/NCNTRL AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020644Z - 020845Z LINEAR MCS CONTINUES TO MOVE FROM ERN OK AND ERN KS TOWARD WRN MO AND NWRN AR EARLY THIS MORNING. BOWING PORTION OF THE LINE WILL BE MOVING ACROSS WS 127 AT 45 KTS INTO SWRN MO AND NWRN AR WITH GUSTY AND POTENTIALLY DAMAGING WIND GUSTS THROUGH 8-9Z. HOWEVER... DIAGNOSTIC DATA SUGGESTS THAT STORMS WILL BECOME MORE ELEVATED AS THEY MOVE EWD INTO THE OZARKS. THUS...IT APPEARS THE SEVERE THREATS WILL DIMINISH WITH TIME AND A NEW WW IS NOT ANTICIPATED DOWNSTREAM INTO CNTRL MO OR NCNTRL AR. ..RACY.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...LZK...SGF...EAX...TSA...TOP...OUN... 39689532 39759370 39229290 38189235 37429218 36499216 35969243 35219362 34909623 36029494 37139460 38619525 WWWW From MCD at goshenarc.org Sun Apr 2 14:42:18 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 10:42:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021441 SWOMCD SPC MCD 021441 MOZ000-IAZ000-KSZ000-NEZ000-021645- MESOSCALE DISCUSSION 0400 NWS STORM PREDICTION CENTER NORMAN OK 0941 AM CDT SUN APR 02 2006 AREAS AFFECTED...NE KS...NW MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021441Z - 021645Z TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A WW...WHICH COULD BECOME NECESSARY BY 18-20Z...IF NOT BEFORE. COLD CORE OF VIGOROUS MID-LEVEL TROUGH IS BEGINNING TO TAKE ON A NEGATIVE TILT ACROSS THE CENTRAL PLAINS. ASSOCIATED FORCING FOR UPWARD VERTICAL MOTION AND DESTABILIZATION IS SUPPORTING ONGOING INCREASING CONVECTIVE DEVELOPMENT...JUST TO THE WEST/SOUTH WEST OF SLOWLY DEEPENING SURFACE LOW AND TRAILING DRY LINE. SURFACE LOW IS CURRENTLY CENTERED NORTH NORTHWEST OF MANHATTAN KS...AND WILL CONTINUE TO GRADUALLY MIGRATE ALONG EASTWARD EXTENDING WARM FRONT ...TOWARD THE ST. JOSEPH MO AREA THROUGH 18Z. INSOLATION IN WARM SECTOR ACROSS NORTHEAST KANSAS INTO NORTHWEST/ WEST CENTRAL MISSOURI WILL BEGIN TO DESTABILIZE BOUNDARY LAYER... BUT ENVIRONMENT ON NOSE OF ELEVATED MIXED LAYER WRAPPING INTO CYCLONE IS ALREADY POTENTIALLY MODERATELY UNSTABLE. AS STRONGER FORCING BEGINS TO OVERSPREAD WARM SECTOR THROUGH MID DAY... INCREASING/INTENSIFYING TRENDS TO CONVECTIVE DEVELOPMENT WILL CONTINUE. LARGE HAIL WILL INITIALLY BE PRIMARY THREAT ACROSS NORTH CENTRAL INTO NORTHEAST KANSAS. BUT...AS ACTIVITY PROGRESSES INTO THE ST. JOSEPH/KANSAS CITY MO AREAS...POTENTIAL FOR DAMAGING WINDS WILL INCREASE AS ACTIVITY BECOMES INCREASINGLY ORGANIZED IN STRONGLY SHEARED CONVECTIVE UNSTABLE ENVIRONMENT. SQUALL LINE MAY BEGIN TO EVOLVE EASTWARD INTO NORTHWESTERN MISSOURI THROUGH THE 18-21Z TIME FRAME. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...DMX...EAX...OAX...TOP...ICT...GID... 40489761 40769613 40669474 40529369 40039297 39399272 38769310 38239372 37749431 37859525 38469562 39079690 39389767 WWWW From MCD at goshenarc.org Sun Apr 2 15:43:11 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 11:43:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021542 SWOMCD SPC MCD 021542 TNZ000-KYZ000-ILZ000-MOZ000-MSZ000-ARZ000-021715- MESOSCALE DISCUSSION 0401 NWS STORM PREDICTION CENTER NORMAN OK 1042 AM CDT SUN APR 02 2006 AREAS AFFECTED...ERN AR...SE MO...WRN KY...WRN TN...NW MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021542Z - 021715Z WW IS NOT ANTICIPATED IN SHORT TERM...BUT TRENDS ARE BEING MONITORED. IN WAKE OF INITIAL WEAKENING SHORT WAVE TROUGH...NOW LIFTING THROUGH THE UPPER MISSISSIPPI VALLEY...AND A MORE SUBTLE SUBTROPICAL STREAM IMPULSE...LIFTING ACROSS EASTERN ARKANSAS TOWARD THE TENNESSEE VALLEY...LOW-LEVEL FLOW HAS VEERED TO WESTERLY ACROSS MISSOURI ARKANSAS. THIS HAS CONTRIBUTED TO INCREASING WARM ADVECTION ON EASTERN FRINGE OF LOW-LEVEL THERMAL RIDGE WRAPPING INTO DEEP SURFACE LOW CENTERED OVER NORTHEAST KANSAS/SOUTHEAST NEBRASKA. AS FORCING SPREADS EASTWARD OF THE OZARKS TOWARD THE MISSOURI RIVER...SCATTERED STORMS CONTINUE TO DEVELOP. WARM SECTOR BOUNDARY LAYER TO THE EAST OF ONGOING ACTIVITY IS WARMING WITH INSOLATION...BUT NOT LIKELY TO BECOME DEEPLY MIXED UNTIL MID/LATE AFTERNOON. THUS...THROUGH THE 18-19Z TIME FRAME SCATTERED CONVECTION SEEMS LIKELY TO REMAIN ROOTED ABOVE INVERSION LAYER. ANY SEVERE THREAT SEEMS LIKELY TO BE LIMITED TO ISOLATED MARGINALLY SEVERE HAIL ASSOCIATED WITH MOST UNSTABLE CAPE TO 1000 J/KG IN FAVORABLY SHEARED ENVIRONMENT. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...MEG...JAN...LSX...LZK... 33809150 33799236 34599269 35529180 36399111 36909100 37499065 37328955 36908839 36348811 35058948 33919107 WWWW From MCD at goshenarc.org Sun Apr 2 16:04:15 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 12:04:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021603 SWOMCD SPC MCD 021603 TXZ000-021800- MESOSCALE DISCUSSION 0402 NWS STORM PREDICTION CENTER NORMAN OK 1103 AM CDT SUN APR 02 2006 AREAS AFFECTED...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021603Z - 021800Z TRENDS ARE BEING MONITORED...WW COULD BECOME NECESSARY SHORTLY. MID-LEVEL HEIGHT FALLS HAVE WEAKENED INHIBITION SUFFICIENTLY FOR INITIAL OF VIGOROUS CONVECTIVE DEVELOPMENT TO THE SOUTH OF WACO. VEERING LOW/MID TROPOSPHERIC FLOW AND SUBSEQUENT COOLING APPEAR LIKELY TO CONTRIBUTE TO FURTHER WEAKENING OF CAP THROUGH EARLY AFTERNOON...IN CONFLUENT LOW-LEVEL FLOW REGIME NORTH/WEST OF WACO INTO THE TYLER/LONGVIEW AREAS. THIS MAY SUPPORT INCREASINGLY WIDESPREAD CONVECTIVE DEVELOPMENT IN ENVIRONMENT WITH MIXED LAYER CAPE OF 2000 TO 3000 J/KG. GIVEN FAVORABLE SHEAR...CONVECTIVE INSTABILITY ASSOCIATED WITH DRY MID-LEVELS WILL BE SUPPORT OF SEVERE STORMS WITH DAMAGING WINDS...IN ADDITION TO LARGE HAIL. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX...SJT... 31009901 31769863 32319735 32889605 33369523 33029433 32029441 31239522 30929703 30429915 WWWW From MCD at goshenarc.org Sun Apr 2 16:35:28 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 12:35:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021634 SWOMCD SPC MCD 021634 MOZ000-021830- MESOSCALE DISCUSSION 0403 NWS STORM PREDICTION CENTER NORMAN OK 1134 AM CDT SUN APR 02 2006 AREAS AFFECTED...CNTRL THROUGH SW/S CNTRL MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021634Z - 021830Z A TORNADO WW WILL PROBABLY BE NEEDED BY AROUND 18Z...OR SHORTLY THEREAFTER. MOISTENING/HEATING OF BOUNDARY LAYER IS CONTRIBUTING TO INCREASING POTENTIAL INSTABILITY IN WARM SECTOR...EAST OF DRY LINE/COLD FRONT TRAILING FROM SLOWLY DEEPENING SURFACE LOW WHICH IS NOW WEST/NORTHWEST OF ST. JOSEPH MO. LEADING EDGE OF STRONGER MID-LEVEL COOLING ALREADY APPEARS TO BE OVERSPREADING DEVELOPING INSTABILITY AXIS...AND INHIBITION IS WEAKENING. THIS MAY BECOME SUPPORTIVE OF NEW BOUNDARY LAYER-BASED CONVECTIVE INITIATION AS EARLY AS 18-20Z SOUTHEAST OF THE KANSAS CITY INTO THE SPRINGFIELD AREA. BROKEN SQUALL LINE SEEMS LIKELY TO QUICKLY EVOLVE...IN ENVIRONMENT WITH MIXED LAYER INCREASING IN EXCESS OF 2000 J/KG. 70 KT MID-LEVEL JET STREAK NOSING INTO THE OZARK PLATEAU WILL CONTRIBUTE TO DEEP LAYER SHEAR SUFFICIENT FOR SUPERCELLS. THOUGH LOW-LEVEL HODOGRAPHS MAY NOT POSSESS STRONG CLOCKWISE CURVATURE...SHEAR BENEATH 30 TO 40 TO WESTERLY 850 FLOW WILL STILL BE SUPPORTIVE OF TORNADIC ACTIVITY...PARTICULARLY IN STRONGER/MORE ISOLATED CELLS WITHIN LINE. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX... 38049433 38719402 39699329 39509222 39159166 38219149 37659170 36779206 36549322 36599383 37069429 WWWW From MCD at goshenarc.org Sun Apr 2 18:15:16 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 14:15:16 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021814 SWOMCD SPC MCD 021814 TNZ000-KYZ000-GAZ000-ALZ000-MSZ000-021945- MESOSCALE DISCUSSION 0404 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT SUN APR 02 2006 AREAS AFFECTED......PARTS OF NE MS/NRN AL AND MIDDLE/EASTERN TN INTO PARTS OF S CNTRL/SE KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021814Z - 021945Z TRENDS CONTINUE TO BE MONITORED FOR INCREASING SEVERE THREAT AND THE POSSIBILITY OF A WW. EMBEDDED WITHIN MODERATELY STRONG MEAN SOUTHWESTERLY FLOW REGIME... SMALL CONVECTIVE CLUSTER APPEARS LIKELY TO BEGIN TO SHIFT AWAY FROM SUPPORTING STRONGER LOW-LEVEL WARM ADVECTION REGIME OVER THE LOWER MISSISSIPPI VALLEY. HOWEVER...MOIST BOUNDARY LAYER AHEAD OF ACTIVITY INTO RETREATING WARM FRONT ALONG THE WESTERN SLOPES OF THE APPALACHIANS CONTINUES TO BECOME MORE DEEPLY MIXED AND SUSCEPTIBLE TO SURFACE-BASED CONVECTIVE DEVELOPMENT. AS CLUSTER SPREADS INTO EXTREME NORTHERN ALABAMA/MIDDLE TENNESSEE BY 20-21Z...THIS MAY OCCUR ALONG LEADING EDGE OF STRENGTHENING SURFACE COLD POOL. GIVEN LIKELY CONTINUED EAST NORTHEAST MOTION OF 40+ KT...TENDENCY FOR STRONG SURFACE GUSTS APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS MAY INCREASE LATE THIS AFTERNOON. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...FFC...LMK...OHX...HUN...PAH...MEG... 35838823 36588764 37268540 36998431 36468407 35668430 35348481 34918552 34638617 34448722 34418761 35008835 WWWW From MCD at goshenarc.org Sun Apr 2 19:16:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 15:16:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021916 SWOMCD SPC MCD 021915 ARZ000-MOZ000-022045- MESOSCALE DISCUSSION 0405 NWS STORM PREDICTION CENTER NORMAN OK 0215 PM CDT SUN APR 02 2006 AREAS AFFECTED...AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021915Z - 022045Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT. A NEW WW MAY BE NEEDED BY AROUND 21Z OR SHORTLY THEREAFTER. WARM SECTOR BOUNDARY LAYER WITH LOWER/MID 60S DEW POINTS IS NOW WARMING INTO THE LOWER 80S ACROSS MUCH OF WESTERN AND CENTRAL ARKANSAS. THIS HAS CONTRIBUTED TO MODERATE INSTABILITY...WITH CAPE INCREASING TO AROUND 2000 J/KG. INFLUENCE OF SUBSIDENCE/DRYING IN BASE OF APPROACHING SHORT WAVE TROUGH IS STILL UNCERTAIN AT THE PRESENT TIME...BUT IT APPEARS CONVECTIVE INITIATION IS NOT AS IMMINENT AS AREAS FARTHER TO THE NORTH. HOWEVER...WITH TIME...MODELS SUGGEST EROSION OF MID-LEVEL INHIBITION BY LATE AFTERNOON WITH LOWER/MID TROPOSPHERIC COOLING AND ADDITIONAL SURFACE HEATING. THIS MAY BECOME SUPPORTIVE OF CONVECTIVE INITIATION AS EARLY AS 21-22Z. STRONG SHEAR NEAR 70 KT MID-LEVEL JET STREAK NOSING INTO THE OZARK PLATEAU WILL CONTRIBUTE TO RAPID SUPERCELL DEVELOPMENT. POTENTIAL FOR VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL EXIST IN STRONGER CELLS. ISOLATED TORNADOES ARE ALSO POSSIBLE. TORNADO POTENTIAL COULD INCREASE LATE THIS AFTERNOON AS ACTIVITY SPREADS FROM CENTRAL INTO EASTERN ARKANSAS...WHERE SURFACE FLOW MAY MAINTAIN A MORE SOUTHERLY COMPONENT AND LARGER LOW-LEVEL HODOGRAPHS. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...JAN...LZK...SGF...SHV... 35569341 36029307 36339245 36519155 36309097 35839067 35009070 34529099 33819118 33219219 33099276 33209379 33769402 34459416 34979381 WWWW From MCD at goshenarc.org Sun Apr 2 20:17:02 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 16:17:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022016 SWOMCD SPC MCD 022016 ILZ000-MOZ000-IAZ000-022145- MESOSCALE DISCUSSION 0406 NWS STORM PREDICTION CENTER NORMAN OK 0316 PM CDT SUN APR 02 2006 AREAS AFFECTED...CNTRL/ERN MO CONCERNING...TORNADO WATCH 130... VALID 022016Z - 022145Z CONTINUE WW. POTENTIAL FOR TORNADOES MAY INCREASE NEXT FEW HOURS ACROSS PARTS OF NORTHEAST/EAST CENTRAL MISSOURI. NEW WW MAY BE NEEDED NORTHEAST OF WW 130 BEFORE 21Z. RAPID CONVECTIVE DEVELOPMENT IS ONGOING ALONG PRE-FRONTAL INSTABILITY AXIS...TRAILING FROM DEEP SOUTHWEST IOWA SURFACE CYCLONE...SOUTHWARD THROUGH THE OZARKS. BROKEN SQUALL LINE WITH EMBEDDED SUPERCELLS WILL CONTINUE TO EVOLVE LATE THIS AFTERNOON... SPREADING EASTWARD AHEAD OF STRONGER MID-LEVEL FORCING THROUGH THE MIDDLE MISSISSIPPI VALLEY. DESPITE LACK OF MORE PRONOUNCED VEERING OF LOW-LEVEL WIND FIELDS IN WARM SECTOR...SHEAR APPEARS STRONG ENOUGH FOR RISK OF TORNADOES IN SUPERCELLS...IN ADDITION TO LARGE HAIL/DAMAGING WIND THREAT ALONG DEVELOPING LINE. BETTER RISK FOR TORNADOES MAY DEVELOP IN THE 21-00Z TIME FRAME...AS SUPERCELLS WITHIN LINE BEGIN TO CROSS OLD WARM FRONTAL ZONE EXTENDING ACROSS THE ST. LOUIS INTO THE QUINCY/OTTUMWA AREAS. WARM FRONT IS BEGINNING TO LIFT NORTH OF THIS REGION...BUT SURFACE WINDS MAY BE SLOWER TO VEER TO A WESTERLY COMPONENT...CONTRIBUTING TO STRONGER CLOCKWISE CURVATURE IN LOW LEVEL HODOGRAPHS. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...LOT...ILX...LSX...DVN...SGF...DMX...EAX... 41039285 41739264 42019165 42089067 41588928 40538889 39498889 38568920 37548986 36739113 36739330 38099278 39829255 WWWW From MCD at goshenarc.org Sun Apr 2 22:03:38 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 18:03:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022202 SWOMCD SPC MCD 022202 TXZ000-022330- MESOSCALE DISCUSSION 0407 NWS STORM PREDICTION CENTER NORMAN OK 0502 PM CDT SUN APR 02 2006 AREAS AFFECTED...NE TX CONCERNING...SEVERE THUNDERSTORM WATCH 129... VALID 022202Z - 022330Z AN ISOLATED LARGE HAIL AND WIND DAMAGE THREAT MAY INCREASE AS STORMS INITIATE AND EXPAND IN COVERAGE EARLY THIS EVENING. A WW MAY BECOME NECESSARY ACROSS THE REGION WITHIN THE NEXT FEW HOURS. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT IN PLACE EXTENDING SWWD FROM SE OK ACROSS THE DALLAS/FORT WORTH AREA. VISIBLE SATELLITE IMAGERY SHOWS TOWERING CUMULUS EVIDENT ALONG AND AHEAD OF THE BOUNDARY. AS A SHORTWAVE TROUGH APPROACHES THE AREA THIS EVENING...SCATTERED STORM INITIATION SHOULD TAKE PLACE DUE TO STRONG CONVERGENCE ALONG THE FRONT AND INCREASING LARGE-SCALE ASCENT. FORECAST SOUNDINGS THROUGH EARLY THIS EVENING SHOW 40 TO 45 KT OF VERTICAL SHEAR WITH LAPSE RATES AROUND 7.0 C/KM. THIS SHOULD BE SUFFICIENT FOR LARGE HAIL AND ISOLATED WIND DAMAGE CONSIDERING MODERATE INSTABILITY EXISTS ACROSS MOST OF NE TX. IF STORM COVERAGE CONTINUES TO SLOWLY INCREASE EARLY THIS EVENING AS MANY OF THE SHORT-TERM MODELS SUGGEST...A NEW WW MAY BECOME NECESSARY ACROSS THE REGION EARLY THIS EVENING. ..BROYLES.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD... 31629426 30959625 31209721 31979706 32889473 32349404 WWWW From MCD at goshenarc.org Sun Apr 2 23:52:32 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 19:52:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022351 SWOMCD SPC MCD 022351 INZ000-ILZ000-030045- MESOSCALE DISCUSSION 0408 NWS STORM PREDICTION CENTER NORMAN OK 0651 PM CDT SUN APR 02 2006 AREAS AFFECTED...ERN IL CONCERNING...TORNADO WATCH 133...137... VALID 022351Z - 030045Z ...MULTIPLE TORNADIC SUPERCELLS WILL RACE NEWD ACROSS ECNTRL IL... MULTIPLE TORNADIC SUPERCELLS ARE EMBEDDED WITHIN AN ELONGATED LINE OF SEVERE THUNDERSTORMS STRETCHING FROM HENRY COUNTY IL...SEWD INTO WAYNE COUNTY IL. A NARROW WEDGE OF UNSTABLE AIR SUPPORTIVE OF MAINTAINING THIS TORNADIC ACTIVITY HAS SPREAD INTO ECNTRL IL/SWRN IND. GIVEN STORM MOTION IS QUITE FAST...APPROACHING 50 KT...THERE IS SOME QUESTION AS TO THE DEGREE OF BOUNDARY LAYER DESTABILIZATION POSSIBLE DOWNSTREAM OVER CNTRL IND. EVEN SO...TORNADIC STRUCTURES AT SOME POINT WILL LIKELY EVOLVE INTO DAMAGING BOW-TYPE FEATURES THAT WILL RACE NEWD ACROSS THE REMAINDER OF WW137 WITH ACTIVITY REACHING WRN OH BY LATE EVENING. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...LOT...ILX...LSX... 37958833 39158899 40528981 41008872 40358664 38768629 WWWW From MCD at goshenarc.org Sun Apr 2 23:59:41 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 19:59:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022359 SWOMCD SPC MCD 022358 KYZ000-TNZ000-ALZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-030130- MESOSCALE DISCUSSION 0409 NWS STORM PREDICTION CENTER NORMAN OK 0658 PM CDT SUN APR 02 2006 AREAS AFFECTED...SRN IL...FAR NE AR...WRN TN AND WRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 134... VALID 022358Z - 030130Z A LINE OF SUPERCELLS ONGOING ACROSS SE MO AND NE AR WILL CONTINUE TO HAVE A THREAT OF TORNADOES...LARGE HAIL AND WIND DAMAGE OVER THE NEXT FEW HOURS. A TORNADO WATCH WILL LIKELY BECOME NECESSARY EAST OF THE CURRENT TORNADO WATCHES. LATEST SFC ANALYSIS SHOWS A LOW-LEVEL MOIST AXIS WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F EXTENDING NWD ACROSS WRN TN AND WRN KY. THIS IS IN THE VICINITY OF A 40 KT LOW-LEVEL JET WHICH WILL CONTINUE TO INCREASE THIS EVENING. THIS COMBINED WITH STRONG LIFT AND VERTICAL SHEAR ASSOCIATED WITH THE NOSE OF A MID-LEVEL JET WILL CONTINUE TO MAKE THE ENVIRONMENT VERY FAVORABLE FOR SUPERCELLS AND TORNADOES. AS THE SUPERCELLS MOVE INTO THE LOW-LEVEL JET...LONG TRACK SIGNIFICANT TORNADOES WILL REMAIN POSSIBLE OVER THE NEXT HOUR. THE SEVERE THREAT SHOULD CONTINUE EWD INTO CNTRL TN AND CNTRL KY AS THE SUPERCELLS TRACK EWD. LARGE HAIL...WIND DAMAGE AND TORNADOES WILL CONTINUE TO BE POSSIBLE THROUGH LATE THIS EVENING. ..BROYLES.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JKL...LMK...OHX...HUN...PAH...MEG... 34928659 35029019 35319072 36359013 37808890 37868570 36978497 35858896 35968989 36289005 36438974 36168848 35848859 WWWW From MCD at goshenarc.org Mon Apr 3 00:08:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 20:08:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030007 SWOMCD SPC MCD 030006 KYZ000-TNZ000-ALZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-030130- MESOSCALE DISCUSSION 0409 NWS STORM PREDICTION CENTER NORMAN OK 0706 PM CDT SUN APR 02 2006 AREAS AFFECTED...SRN IL...FAR NE AR...WRN TN AND WRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 134... VALID 030006Z - 030130Z A LINE OF SUPERCELLS ONGOING ACROSS SE MO AND NE AR WILL CONTINUE TO HAVE A THREAT OF TORNADOES...LARGE HAIL AND WIND DAMAGE OVER THE NEXT FEW HOURS. A TORNADO WATCH WILL LIKELY BECOME NECESSARY EAST OF THE CURRENT TORNADO WATCHES. LATEST SFC ANALYSIS SHOWS A LOW-LEVEL MOIST AXIS WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F EXTENDING NWD ACROSS WRN TN AND WRN KY. THIS IS IN THE VICINITY OF A 40 KT LOW-LEVEL JET WHICH WILL CONTINUE TO INCREASE THIS EVENING. THIS COMBINED WITH STRONG LIFT AND VERTICAL SHEAR ASSOCIATED WITH THE NOSE OF A MID-LEVEL JET WILL CONTINUE TO MAKE THE ENVIRONMENT VERY FAVORABLE FOR SUPERCELLS AND TORNADOES. AS THE SUPERCELLS MOVE INTO THE LOW-LEVEL JET...LONG TRACK SIGNIFICANT TORNADOES WILL REMAIN POSSIBLE OVER THE NEXT HOUR. THE SEVERE THREAT SHOULD CONTINUE EWD INTO CNTRL TN AND CNTRL KY AS THE SUPERCELLS TRACK EWD. LARGE HAIL...WIND DAMAGE AND TORNADOES WILL CONTINUE TO BE POSSIBLE THROUGH LATE THIS EVENING. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JKL...LMK...OHX...HUN...PAH...MEG... 34928659 35029019 35319072 36359013 37808890 37868570 36978497 WWWW From MCD at goshenarc.org Mon Apr 3 02:12:02 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 22:12:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030211 SWOMCD SPC MCD 030210 KYZ000-TNZ000-030415- MESOSCALE DISCUSSION 0410 NWS STORM PREDICTION CENTER NORMAN OK 0910 PM CDT SUN APR 02 2006 AREAS AFFECTED...WRN KY...MIDDLE/WRN TN CONCERNING...TORNADO WATCH 134...137...138... VALID 030210Z - 030415Z ...MULTIPLE DISCRETE TORNADIC SUPERCELLS HAVE EVOLVED ACROSS THE REGION... 00Z SOUNDING FROM LZK SUGGESTS HIGH QUALITY LAPSE RATE/INSTABILITY ENVIRONMENT IS SPREADING DOWNSTREAM ACROSS THE TN VALLEY WHERE MULTIPLE DISCRETE TORNADIC SUPERCELLS PERSIST. SEVERAL OF THESE STORMS ARE LONG-LIVED AND HAVE YET TO EXHIBIT ANY SIGNIFICANT WEAKENING. OVER THE LAST FEW HOURS...DIAGNOSTIC TRENDS ARE SHOWING RAPID RECOVERY INTO MIDDLE TN WHERE SIG TOR VALUES ARE NOW APPROACHING 8. TORNADIC THREAT REMAINS HIGH ACROSS THIS REGION FOR THE NEXT FEW HOURS...WITH THE POTENTIAL FOR STRONG TORNADOES. ..DARROW.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...PAH...MEG... 36118910 37458664 36738576 35728657 35048830 35088961 WWWW From MCD at goshenarc.org Mon Apr 3 02:28:06 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 22:28:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030227 SWOMCD SPC MCD 030227 OHZ000-KYZ000-INZ000-030400- MESOSCALE DISCUSSION 0411 NWS STORM PREDICTION CENTER NORMAN OK 0927 PM CDT SUN APR 02 2006 AREAS AFFECTED...ERN IN / CENTRAL AND NRN KY / OH / WRN WV CONCERNING...CONVECTIVE TRENDS VALID 030227Z - 030400Z INTENSE BOW ECHO CONTINUES TO MOVE EWD AT OVER 55 KTS ACROSS ERN INDIANA INTO NRN KY. RADAR PRESENTATION CONTINUES TO SHOW REAR INFLOW JET REFLECTION WITH LOW REFLECTIVITY HOLE JUST BEHIND MAIN BOW...SUGGESTING INTENSE AND WIDESPREAD WIND DAMAGE IS LIKELY. SWLY LOW LEVEL JET WILL CONTINUE TO ADVECT UNSTABLE AIR NEWD INTO OH AND WRN WV. EXTRAPOLATION SHOWS BOW INTO CENTRAL OH BY 4Z. ADDITIONALLY...THREAT FOR TORNADOES CONTINUES GIVEN VERY STRONG EXTREME SHEAR IN PLACE...WITH EITHER EMBEDDED ROTATION SIGNATURES WITHIN LINE OR WITH WARM ADVECTION CELLS AHEAD OF LINE. GREATEST TORNADO THREAT APPEARS TO BE OVER KY IN CLOSER PROXIMITY TO GREATER INSTABILITY. ..JEWELL.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...LMK...IWX...IND... 39178558 40748636 41418590 41588362 41288267 39728204 37768291 37558607 WWWW From MCD at goshenarc.org Mon Apr 3 03:45:34 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 23:45:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030344 SWOMCD SPC MCD 030344 WVZ000-OHZ000-KYZ000-030415- MESOSCALE DISCUSSION 0412 NWS STORM PREDICTION CENTER NORMAN OK 1044 PM CDT SUN APR 02 2006 AREAS AFFECTED...SERN OH / WRN WV / ERN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030344Z - 030415Z A SEVERE THUNDERSTORM WATCH WILL BE ISSUED SHORTLY FOR PORTIONS OF OH...KY...AND WV. LINE OF THUNDERSTORMS CONTINUES TO MOVE EWD ACROSS THE REGION. WIND SPEEDS OVER 70 MPH WERE RECENTLY MEASURED OVER NRN KY. DESPITE RELATIVELY WEAK INSTABILITY AND VILS...FORCING REMAIN STRONG AS REFLECTED IN SURFACE PRESSURE RISE/FALL COUPLET. ..JEWELL.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...PBZ...RLX...JKL...ILN... 37518348 39908350 40048060 37818076 WWWW From MCD at goshenarc.org Mon Apr 3 05:40:52 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 01:40:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030539 SWOMCD SPC MCD 030539 ALZ000-030715- MESOSCALE DISCUSSION 0413 NWS STORM PREDICTION CENTER NORMAN OK 1239 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030539Z - 030715Z SEVERE TSTM RISK WILL INCREASE ACROSS NRN AL AFTER 07Z. A WW WILL LIKELY BE REQUIRED. A BAND OF TSTMS CONTINUES TO MOVE ACROSS SRN PORTIONS OF WRN/MIDDLE TN AND EXTREME NRN MS EARLY THIS MORNING. EMBEDDED WITHIN THE LINE WERE SEVERAL SUPERCELLS WITH LOW-LEVEL CIRCULATIONS. THE PORTION OF THE LINE ACROSS NRN MS IS EXPECTED TO APPROACH THE NWRN TIP OF AL BY 07Z. FORECAST RUC SOUNDINGS SUGGEST THE AIR MASS ACROSS NRN AL WILL DESTABILIZE GRADUALLY AHEAD OF THE STORMS AND SHOULD SUPPORT SFC-BASED STORMS. HTX HODOGRAPH SHOWS 40+ KT SFC-1KM SHEAR DESPITE A VEERED FLOW REGIME. ALONG WITH THE THREAT FOR DAMAGING WINDS...TORNADOES WILL BE POSSIBLE ALONG WITH HAIL. GIVEN INCREASING RISK FOR SEVERE...A WW WILL LIKELY BE REQUIRED BY 07Z FOR NRN AL. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN... 34888796 34878569 33788549 33808811 WWWW From MCD at goshenarc.org Mon Apr 3 07:17:19 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 03:17:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030716 SWOMCD SPC MCD 030716 NCZ000-SCZ000-TNZ000-GAZ000-030845- MESOSCALE DISCUSSION 0414 NWS STORM PREDICTION CENTER NORMAN OK 0216 AM CDT MON APR 03 2006 AREAS AFFECTED...SRN APPALACHIANS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030716Z - 030845Z A DAMAGING WIND/HAIL THREAT MAY INCREASE ACROSS WRN NC...UPSTATE SC AND PARTS OF NRN GA AFTER 08-09Z. AS A RESULT...A WW MAY BECOME REQUIRED...STAYING N OF THE ATLANTA METRO AREA. A SW-NE ORIENTED LINE OF TSTMS CONTINUES TO SETTLE ESEWD ACROSS ERN/SRN TN THIS MORNING WITH COLD POOL DYNAMICS INCREASING. TSTMS ARE EMBEDDED IN A STRONG WSWLY UNIDIRECTIONAL FLOW REGIME. THIS WILL CONTINUE TO BE FAVORABLE FOR LINE SEGMENTS TO BOW WITH LOCAL ACCELERATION OF WIND GUSTS...PARTICULARLY ACROSS NRN GA WHERE AIR MASS IS A LITTLE MORE UNSTABLE THAN FARTHER NE. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 34878535 35688366 36008207 35728160 34928175 34158443 34068526 WWWW From MCD at goshenarc.org Mon Apr 3 07:59:19 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 03:59:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030757 SWOMCD SPC MCD 030757 MSZ000-030900- MESOSCALE DISCUSSION 0415 NWS STORM PREDICTION CENTER NORMAN OK 0257 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN MS CONCERNING...TORNADO WATCH 141... VALID 030757Z - 030900Z WT 151 IS SET TO EXPIRE AT 09Z AND TSTMS SHOULD MOVE OUT OF THE WATCH BY THEN. THERE WILL BE AN ISOLD DAMAGING WIND/HAIL/TORNADO THREAT DOWNSTREAM INTO PARTS OF NRN MS NEAR/N OF KGTR BETWEEN 0830-0900Z JUST S OF THE CURRENT WATCH. WRN PORTION OF THE SW-NE ORIENTED LINE OF STORMS WAS BEGINNING TO WEAKEN ACROSS SERN AR AND NWRN MS EARLY THIS MORNING. HOWEVER...STRONG TSTMS CONTINUE ACROSS NCNTRL-NERN MS EWD INTO NRN AL. TSTMS ARE EMBEDDED IN A FAST UNIDIRECTIONAL WSWLY FLOW REGIME AND COULD BECOME FAVORABLY ALIGNED TO PRODUCE DAMAGING WINDS AS THEY MOVE ESEWD TOWARD AREAS NEAR/N OF KGTR. OTHERWISE...ACCAS BAND AHEAD OF THE LINE WAS BEGINNING TO SPROUT INTO TSTMS ACROSS CNTRL MS NEWD INTO NCNTRL AL. THESE STORMS ARE DEVELOPING IN A STRONG WARM ADVECTION REGIME. THOUGH THEY MAY TEND TO BE ELEVATED /LARGE HAIL THREAT/...THEY COULD ROOT INTO THE BOUNDARY LAYER AND BEGIN TO PRODUCE DAMAGING WINDS...PARTICULARLY AS THEY MOVE INTO CNTRL/NRN AL. CURRENT INDICATIONS ARE THAT ANOTHER WW WILL NOT BE REQUIRED ACROSS CNTRL MS GIVEN THAT MAJORITY OF THE MASS CONVERGENCE IS POINTING MORE TOWARD THE SRN APPALACHIANS. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...JAN... 33799039 34248855 33918833 33418843 33078977 WWWW From MCD at goshenarc.org Mon Apr 3 10:13:25 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 06:13:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031010 SWOMCD SPC MCD 031010 NCZ000-SCZ000-GAZ000-TNZ000-ALZ000-031215- MESOSCALE DISCUSSION 0416 NWS STORM PREDICTION CENTER NORMAN OK 0510 AM CDT MON APR 03 2006 AREAS AFFECTED...CNTRL/ERN AL...NRN/CNTRL GA...WRN SC...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031010Z - 031215Z HIGHEST PROBABILITY FOR LARGE HAIL...DAMAGING WINDS...AND PERHAPS A TORNADO OR TWO WILL EXIST ACROSS ECNTRL AL NEWD ACROSS CNTRL/NRN GA THROUGH MID-MORNING. A STRONG MID-LEVEL JET STREAK CONTINUED TO TRANSLATE EWD ACROSS THE MID-SOUTH AT DAYBREAK...WITH THE STRONGEST LARGE SCALE ASCENT SPREADING INTO THE SRN APPALACHIANS. THE TSTMS THAT GREW UPSCALE INTO A LINEAR MCS OVERNIGHT...CONTINUE TO MOVE ESEWD ACROSS THE SRN APPALACHIANS AT 10Z. DESPITE STRONG LOW/MID-LEVEL SHEAR...COLD OUTFLOW HAS TENDED TO DOMINATE THE STORMS THROUGH THE MORNING...LESSENING THE RISK FOR TORNADOES. BUT...PLUME OF STEEP MID-TROPOSPHERIC LAPSE RATES SPREADING EWD FROM THE HIGH PLAINS WAS SUPPORTING LARGE HAIL. AS THE MID-LEVEL JET STREAK DEVELOPS EWD THROUGH THE MID-MORNING HOURS...TSTMS SHOULD INTENSIFY ACROSS NRN/CNTRL GA AND MOVE EWD INTO PARTS OF SC. INCREASED BOUNDARY LAYER HEATING WILL BOOST BUOYANCY AND TSTMS MAY BEGIN TO POSE MORE OF A DAMAGING WIND/TORNADO THREATS IN A FEW HOURS. STRONG WSWLY UNIDIRECTIONAL FLOW REGIME WILL ENCOURAGE BOW ECHOES AND SUPERCELLS. UPSTREAM...TSTMS WILL TEND TO BACKBUILD INTO PARTS OF AL INTO THE STEEPER MID-LEVEL LAPSE RATES. THESE STORMS WILL TEND TO BE MORE OF A LARGE HAIL THREAT. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...GSP...MRX...FFC...BMX... 33118830 34098574 34978471 35348281 35878187 35858054 34558096 33758171 32188322 32018566 WWWW From MCD at goshenarc.org Mon Apr 3 13:35:10 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 09:35:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031334 SWOMCD SPC MCD 031334 NCZ000-SCZ000-031500- MESOSCALE DISCUSSION 0417 NWS STORM PREDICTION CENTER NORMAN OK 0834 AM CDT MON APR 03 2006 AREAS AFFECTED...NC...SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031334Z - 031500Z A LINE OF ELEVATED THUNDERSTORMS IS CURRENTLY ONGOING IN THE FOOTHILLS OF THE APPALACHIAN MTNS IN CNTRL NC. AS THE LINE GRADUALLY INTENSIFIES OVER THE NEXT FEW HOURS...THE THREAT FOR LARGE HAIL AND ISOLATED WIND DAMAGE WILL LIKELY INCREASE. A NEW WW MAY BECOME NECESSARY BY 14 TO 15Z. WATER VAPOR IMAGERY CURRENTLY SHOWS A POTENT UPPER-LEVEL TROUGH MOVING EWD INTO THE REGION WITH THE RUC GRADUALLY INCREASING LARGE-SCALE ASCENT OVER THE NEXT FEW HOURS ACROSS THE CAROLINAS. THIS SHOULD CONTINUE TO SUPPORT AN INCREASE IN STORM COVERAGE WITH STORMS EXPANDING SWD WITH TIME. THE GSO 12Z SOUNDING HAS SOME INSTABILITY MAINLY ABOVE 700 MB WITH LAPSE RATES FROM 700-500 MB LAPSE RATES EXCEEDING 7.0 C/KM. AS SFC HEATING CONTINUES AHEAD OF THE LINE THIS MORNING...LAPSE RATES SHOULD CONTINUE TO STEEPEN. THIS COMBINED WITH MODERATE VERTICAL SHEAR AND INCREASING INSTABILITY SHOULD RESULT IN A POTENTIAL FOR LARGE HAIL. AS THE CONVECTION MOVES EWD AND BECOMES MORE SFC-BASED AROUND MID-DAY...THERE WILL BE AN INCREASING THREAT FOR WIND DAMAGE AND TORNADOES. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CAE...GSP... 36217813 36007746 35597730 35117762 34277905 33588048 33648121 34098159 34488147 35348000 35987888 WWWW From Mcd at goshenarc.org Mon Apr 3 14:05:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 10:05:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031404 SWOMCD SPC MCD 031404 PAZ000-WVZ000-OHZ000-031530- MESOSCALE DISCUSSION 0418 NWS STORM PREDICTION CENTER NORMAN OK 0904 AM CDT MON APR 03 2006 AREAS AFFECTED...ERN PA...NRN WV...WRN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031404Z - 031530Z THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS SRN OH. AS THE STORMS EXPAND AND MOVE NEWD...A LARGE HAIL...WIND DAMAGE AND ISOLATED TORNADO THREAT WILL LIKELY DEVELOP OVER THE NEXT FEW HOURS. A WW SHOULD BECOME NECESSARY LATER THIS MORNING ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LOW OVER SRN MI WITH A POTENT TROUGH EXTENDING SWD ACROSS THE OH RIVER VALLEY. A STRONG BAND OF LARGE-SCALE ASCENT ASSOCIATED WITH THE TROUGH WILL SPREAD NEWD ACROSS ERN OH INTO WRN PA LATE THIS MORNING ALLOWING FOR THUNDERSTORM ACTIVITY TO EXPAND IN COVERAGE. OTHER STORMS SHOULD INITIATE ACROSS SW OH AND SPREAD EWD ACROSS THE SRN OH LATE THIS MORNING. VISIBLE IMAGERY SHOWS PARTIALLY CLEAR SKIES EXTENDING NNEWD FROM NRN KY ACROSS ERN OH WHICH SHOULD ALLOW FOR QUICK DESTABILIZATION THIS MORNING. THIS COMBINED WITH STEEP LAPSE RATES...MODERATE VERTICAL SHEAR AND COLD TEMPS ALOFT SHOULD SUPPORT A THREAT FOR SUPERCELLS WITH LARGE HAIL. AS THE STORMS INTENSIFY AND LOW-LEVEL LAPSE RATES STEEPEN...WIND DAMAGE AND AN AND ISOLATED TORNADO THREAT WILL BECOME POSSIBLE. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...PBZ...RLX...CLE...ILN... 40608289 41088201 41618002 41867894 41297817 40467812 39598023 39248190 39438268 40138297 WWWW From Mcd at goshenarc.org Mon Apr 3 14:25:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 10:25:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031424 SWOMCD SPC MCD 031424 COR PAZ000-MDZ000-WVZ000-OHZ000-031530- MESOSCALE DISCUSSION 0418 NWS STORM PREDICTION CENTER NORMAN OK 0924 AM CDT MON APR 03 2006 AREAS AFFECTED...ERN OH...NRN WV...WRN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031424Z - 031530Z CORRECTED FOR STATE LIST AT TOP THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS SRN OH. AS THE STORMS EXPAND AND MOVE NEWD...A LARGE HAIL...WIND DAMAGE AND ISOLATED TORNADO THREAT WILL LIKELY DEVELOP OVER THE NEXT FEW HOURS. A WW SHOULD BECOME NECESSARY LATER THIS MORNING ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LOW OVER SRN MI WITH A POTENT TROUGH EXTENDING SWD ACROSS THE OH RIVER VALLEY. A STRONG BAND OF LARGE-SCALE ASCENT ASSOCIATED WITH THE TROUGH WILL SPREAD NEWD ACROSS ERN OH INTO WRN PA LATE THIS MORNING ALLOWING FOR THUNDERSTORM ACTIVITY TO EXPAND IN COVERAGE. OTHER STORMS SHOULD INITIATE ACROSS SW OH AND SPREAD EWD ACROSS THE SRN OH LATE THIS MORNING. VISIBLE IMAGERY SHOWS PARTIALLY CLEAR SKIES EXTENDING NNEWD FROM NRN KY ACROSS ERN OH WHICH SHOULD ALLOW FOR QUICK DESTABILIZATION THIS MORNING. THIS COMBINED WITH STEEP LAPSE RATES...MODERATE VERTICAL SHEAR AND COLD TEMPS ALOFT SHOULD SUPPORT A THREAT FOR SUPERCELLS WITH LARGE HAIL. AS THE STORMS INTENSIFY AND LOW-LEVEL LAPSE RATES STEEPEN...WIND DAMAGE AND AN AND ISOLATED TORNADO THREAT WILL BECOME POSSIBLE. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...LWX...PBZ...RLX...CLE...ILN... 40107790 39267984 38808170 38778282 38798299 39548345 40498348 41128204 41618002 41867894 41297817 40467812 WWWW From Mcd at goshenarc.org Mon Apr 3 15:57:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 11:57:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031556 SWOMCD SPC MCD 031555 SCZ000-GAZ000-ALZ000-031800- MESOSCALE DISCUSSION 0419 NWS STORM PREDICTION CENTER NORMAN OK 1055 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN GA...SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031555Z - 031800Z THUNDERSTORM INITIATION APPEARS LIKELY EARLY THIS AFTERNOON ACROSS NRN GA AND/OR FAR NE AL. AS STORMS DEVELOP...SUPERCELLS WILL HAVE A POTENTIAL FOR LARGE HAIL AND WIND DAMAGE WITH TORNADOES BECOMING INCREASINGLY POSSIBLE AS STORMS DRIFT EWD INTO ERN GA AND WRN SC. A WW WILL LIKELY BE NECESSARY AROUND MIDDAY AS STORMS INITIATE AND INCREASE IN COVERAGE. WATER VAPOR IMAGERY CURRENTLY SHOWS A POTENT UPPER-LEVEL TROUGH OVER THE TN VALLEY WITH RUC FORECASTS MOVING A STRONG VORTICITY MAX EWD ACROSS NRN GA OVER THE NEXT FEW HOURS. AS LARGE-SCALE ASCENT INCREASES...MODERATE INSTABILITY DEVELOPS ACROSS THE REGION AND LOW-LEVEL CONVERGENCE BECOMES ENHANCED...STORM INITIATION SHOULD OCCUR IN NRN GA AND/OR FAR NE AL. INITIALLY STORM DEVELOPMENT SHOULD OCCUR IN THE HIGHER TERRAIN NORTH OF ATLANTA BUT ADDITIONAL STORMS MAY INITIATE FURTHER SOUTH IN NCNTRL GA. FORECAST SOUNDINGS IN NRN GA FOR THIS AFTERNOON SHOW STRONG VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL AND WIND DAMAGE WILL BE LIKELY. IN ADDITION...STRONG LOW-LEVEL SPEED SHEAR ASSOCIATED WITH A 40 KT LOW-LEVEL JET SHOULD BE FAVORABLE FOR TORNADOES AS SUPERCELLS MATURE AND MOVE EWD INTO ERN GA AND WRN SC LATER THIS AFTERNOON. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...CAE...GSP...FFC...BMX...HUN... 33188073 33018174 33128367 33398514 33978568 34568569 34818518 34808404 34488081 33318062 WWWW From Mcd at goshenarc.org Mon Apr 3 18:17:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:17:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031815 SWOMCD SPC MCD 031814 PAZ000-NYZ000-MDZ000-WVZ000-VAZ000-OHZ000-032015- MESOSCALE DISCUSSION 0420 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR SERN OH...WRN AND CENTRAL PA...SWRN NY AND ERN/CENTRAL WV...NWRN VA...PANDHANDLE OF MD CONCERNING...TORNADO WATCH 146... VALID 031814Z - 032015Z ORGANIZED LINE OF CONVECTION MOVING THROUGH WRN PA WILL CONTINUE TO POSE A THREAT FOR MAINLY DMGG WINDS OVER THE NEXT FEW HRS. AN ISOLATED TORNADO IS ALSO POSSIBLE WITHIN THIS LINE. FURTHER SW..MORE CELLULAR CONVECTION OVER CENTRAL WV AND FAR SERN OH SHOULD CONTINUE TO GRADUALLY INTENSIFY AND MAY BEGIN TO POSE A THREAT FOR ISOLATED TORNADOES AND SVR WINDS/HAIL. AREAS DOWNWIND OF TORNADO WW 146...CENTRAL PA AND ERN WV/WRN MD/VA...WILL BE MONITORED FOR DESTABILIZING TRENDS OVER THE NEXT COUPLE HRS. LATEST RADAR DATA SHOWS AN ORGANIZED LINE OF STG-SVR STORMS OVER WRN PA MOVING ENEWD AROUND 30 KTS. EXTRAPOLATION OF THIS LINE MOTION TAKE THE LINE OUT OF WW 146 INTO CENTRAL PA AROUND 19Z. ATTM THE AIRMASS DOWNSTREAM OVER CENTRAL PA IS ONLY MARGINALLY UNSTABLE WITH MUCAPES FROM 100-300 J/KG AND TEMPERATURES IN THE 50S. RECENT VISIBLE SATELLITE TRENDS AND CURRENT FCST SOUNDINGS INDICATE THAT INSTABILITY SHOULD NOT INCREASE SUBSTANTIALLY IN THIS AREA AHEAD OF THE CONVECTIVE LINE. THIS SHOULD AID IN A DECREASING TREND IN THE SEVERITY OF THE CONVECTIVE LINE AS IT MOVES INTO CENTRAL PA. FURTHER NORTH...SLIGHTLY HIGHER INSTABILITY OVER SWRN NY MAY SUPPORT A MARGINAL SVR THREAT WITH CONVECTIVE LINE OVER THE NEXT FEW HRS. FURTHER SOUTH...WLY FLOW INCREASING OVER THE CENTRAL APPALACHIANS HAS LEAD TO SUBSIDENCE AND DRYING OVER THE LOWER ELEVATIONS OF ERN WV AND NWRN VA. CONVECTION THAT WAS INTENSIFYING OVER CENTRAL WV MAY TEND TO WEAKEN SOME AS IT MOVES INTO THIS WEAKER INSTABILITY AREA AND OUT OF WW 146. WE WILL MONITOR TRENDS FOR THE NEED FOR AN ADDITIONAL WATCH IN THIS AREA AS WELL. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BGM...BUF...CTP...LWX...PBZ...RLX...CLE... 42027747 43157833 42947907 42387988 41998062 41478092 40348104 39118120 38858111 38428096 38268017 38357872 39267785 40417755  From Mcd at goshenarc.org Mon Apr 3 18:38:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:38:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031836 SWOMCD SPC MCD 031836 NCZ000-VAZ000-032030- MESOSCALE DISCUSSION 0421 NWS STORM PREDICTION CENTER NORMAN OK 0136 PM CDT MON APR 03 2006 AREAS AFFECTED...SRN VA...NRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031836Z - 032030Z STORM INITIATION WILL BECOME INCREASINGLY LIKELY FROM NRN NC INTO SRN VA AS DESTABILIZATION OCCURS THIS AFTERNOON. THE ENVIRONMENT WILL BECOME FAVORABLE FOR SUPERCELLS WITH A POTENTIAL FOR TORNADOES...LARGE HAIL AND WIND DAMAGE. A WW MAY BE NEEDED BY MID TO LATE AFTERNOON ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS A STRONG UPPER-LEVEL TROUGH ENTERING THE APPALACHIAN MTNS. LARGE-SCALE ASCENT WILL MARKEDLY INCREASE AS THE TROUGH BEGINS TO AFFECT THE FOOTHILLS OF VA AND NC THIS AFTERNOON. IN ADDITION...VISIBLE IMAGERY SHOWS CUMULUS BEGINNING TO FORM ALONG A MESOSCALE THERMAL AXIS EXTENDING NWD FROM GREENSBORO NC TO ROANOKE VA. ALTHOUGH THE AREA REMAINS CAPPED AND WEAKLY UNSTABLE...DESTABILIZATION WILL CONTINUE DUE TO SFC HEATING. IN ADDITION...LOW-LEVEL CONVERGENCE SHOULD BECOME ENHANCED LATE THIS AFTERNOON WHICH COMBINED INCREASING ASCENT FROM THE WEST SHOULD SUPPORT STORM INITIATION. INITIATION WOULD BE MOST LIKELY ALONG THE THERMAL AXIS IN THE 20Z TO 22Z TIMEFRAME. CLEARING ON VISIBLE IMAGERY SHOULD ALLOW MODERATE INSTABILITY TO DEVELOP BY LATE AFTERNOON WHICH COMBINED WITH 50 KT OF VERTICAL SHEAR WILL BE FAVORABLE FOR SUPERCELLS. IN ADDITION...A 40 KT LOW-LEVEL JET CURRENTLY FORMING OVER NRN NC EVIDENT ON OBJECTIVE ANALYSIS COMBINED WITH BACKED SFC WINDS ALONG THE NC-VA STATE-LINE WILL BE INCREASINGLY FAVORABLE FOR TORNADOES AS SUPERCELLS DEVELOP AND TRACK EWD INTO SE VA AND NE NC BY EARLY THIS EVENING. LARGE HAIL AND WIND DAMAGE WILL ALSO BE LIKELY WITH SUPERCELLS AS LAPSE RATES STEEPEN DUE TO THE APPROACH OF THE UPPER-LEVEL TROUGH. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...GSP... 35347698 35117848 35227996 35768049 36148061 36778064 37198032 37557918 37557731 37377641 36837607 36217602 35727610  From Mcd at goshenarc.org Mon Apr 3 18:45:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:45:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031842 SWOMCD SPC MCD 031842 TXZ000-032045- MESOSCALE DISCUSSION 0422 NWS STORM PREDICTION CENTER NORMAN OK 0142 PM CDT MON APR 03 2006 AREAS AFFECTED...SCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031842Z - 032045Z TOWERING CU WAS DEVELOPING ALONG A STATIONARY BOUNDARY OVER SCENTRAL TX FROM THE DRT AREA EWD TO NEAR SAT AND AUS AREA. MODERATE-STG INSTABILITY WILL AID IN POTENTIAL FOR ISOLATED SVR WIND/HAIL... DESPITE MARGINAL VERTICAL WIND SHEAR. LATEST SFC ANALYSIS INDICATES A STATIONARY FRONT EXTENDING FROM NEAR DRT EWD TO JUST SOUTH OF KERRVILLE EWD TO BASTROP COUNTY. MODERATE INSTABILITY WITH MLCAPES AROUND 2000 J/KG EXISTED ALONG AND SOUTH OF THIS BOUNDARY. ALTHOUGH CONVERGENCE IS RELATIVELY WEAK ALONG THE BOUNDARY...CONTINUED DAYTIME HEATING SHOULD AID IN AT LEAST AN ISOLATED TSTM DEVELOPMENT. GIVEN THE DEGREE OF INSTABILITY AND STEEP LOW-MID LVL LAPSE RATES...THERE WILL BE SOME POTENTIAL FOR ISOLATED SVR HAIL/WIND AS STORMS MOVE SEWD AROUND 15 KTS. RELATIVELY WEAK MID LEVEL WINDS WILL BE SOMEWHAT OFFSET BY ELY LOW LEVEL WINDS...ENHANCING VERTICAL SHEAR. HOWEVER...SHEAR SHOULD REMAIN LOW ENOUGH THAT AN ORGANIZED SVR THREAT IS NOT ANTICIPATED. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842  From Mcd at goshenarc.org Mon Apr 3 21:00:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 17:00:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032059 SWOMCD SPC MCD 032059 NCZ000-SCZ000-032230- MESOSCALE DISCUSSION 0423 NWS STORM PREDICTION CENTER NORMAN OK 0359 PM CDT MON APR 03 2006 AREAS AFFECTED...NRN SC AND CNTRL NC CONCERNING...SEVERE THUNDERSTORM WATCH 147... VALID 032059Z - 032230Z SEVERAL SUPERCELLS ARE ONGOING ACROSS THE ERN PART OF WW 147. LARGE HAIL AND WIND DAMAGE WILL BE LIKELY WITH THE STORMS OVER THE NEXT FEW HOURS. TORNADOES WILL ALSO BE POSSIBLE WITH THE STRONGER SUPERCELLS AS THE STORMS TRACK EWD INTO NERN SC AND SCNTRL NC BY EARLY EVENING. WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A STRONG VORTICITY MAX IN NRN VA WITH A BAND OF WELL-FOCUSED LARGE-SCALE ASCENT MOVING ACROSS THE WRN CAROLINAS ATTM. THE SUPERCELLS ARE ONGOING ALONG THE LEADING EDGE OF ASCENT JUST AHEAD OF A 70 KT MID-LEVEL JET. THE LIFT COMBINED WITH STEEPENING LAPSE RATES AND THE RELATIVELY DRY BOUNDARY LAYER (SFC DEWPOINTS IN THE 40S F) WILL FAVOR WIND DAMAGE AND LARGE HAIL. THE WIND DAMAGE POTENTIAL WILL BE ENHANCED WEST OF I-77 WHERE SFC TEMP-DEWPOINT DEPRESSIONS EXCEED 30 DEGREES F. AS THE SUPERCELLS MOVE EWD INTO NERN SC AND SCNTRL NC...THE TORNADO POTENTIAL WILL INCREASE SOME DUE TO GREATER LOW-LEVEL MOISTURE WHERE SFC DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 50S F. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...ILM...CAE...GSP... 35498158 35988112 36087935 35727868 34627859 34177968 33848103 33928134 34198188 34998197 WWWW From Mcd at goshenarc.org Mon Apr 3 23:30:53 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 19:30:53 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032330 SWOMCD SPC MCD 032329 TXZ000-040130- MESOSCALE DISCUSSION 0424 NWS STORM PREDICTION CENTER NORMAN OK 0629 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR SERN OH...WRN AND CENTRAL PA...SWRN NY AND ERN/CENTRAL WV...NWRN VA...PANDHANDLE OF MD CONCERNING...TORNADO WATCH 146... VALID 032329Z - 040130Z ORGANIZED LINE OF CONVECTION MOVING THROUGH WRN PA WILL CONTINUE TO POSE A THREAT FOR MAINLY DMGG WINDS OVER THE NEXT FEW HRS. AN ISOLATED TORNADO IS ALSO POSSIBLE WITHIN THIS LINE. FURTHER SW..MORE CELLULAR CONVECTION OVER CENTRAL WV AND FAR SERN OH SHOULD CONTINUE TO GRADUALLY INTENSIFY AND MAY BEGIN TO POSE A THREAT FOR ISOLATED TORNADOES AND SVR WINDS/HAIL. AREAS DOWNWIND OF TORNADO WW 146...CENTRAL PA AND ERN WV/WRN MD/VA...WILL BE MONITORED FOR DESTABILIZING TRENDS OVER THE NEXT COUPLE HRS. LATEST RADAR DATA SHOWS AN ORGANIZED LINE OF STG-SVR STORMS OVER WRN PA MOVING ENEWD AROUND 30 KTS. EXTRAPOLATION OF THIS LINE MOTION TAKE THE LINE OUT OF WW 146 INTO CENTRAL PA AROUND 19Z. ATTM THE AIRMASS DOWNSTREAM OVER CENTRAL PA IS ONLY MARGINALLY UNSTABLE WITH MUCAPES FROM 100-300 J/KG AND TEMPERATURES IN THE 50S. RECENT VISIBLE SATELLITE TRENDS AND CURRENT FCST SOUNDINGS INDICATE THAT INSTABILITY SHOULD NOT INCREASE SUBSTANTIALLY IN THIS AREA AHEAD OF THE CONVECTIVE LINE. THIS SHOULD AID IN A DECREASING TREND IN THE SEVERITY OF THE CONVECTIVE LINE AS IT MOVES INTO CENTRAL PA. FURTHER NORTH...SLIGHTLY HIGHER INSTABILITY OVER SWRN NY MAY SUPPORT A MARGINAL SVR THREAT WITH CONVECTIVE LINE OVER THE NEXT FEW HRS. FURTHER SOUTH...WLY FLOW INCREASING OVER THE CENTRAL APPALACHIANS HAS LEAD TO SUBSIDENCE AND DRYING OVER THE LOWER ELEVATIONS OF ERN WV AND NWRN VA. CONVECTION THAT WAS INTENSIFYING OVER CENTRAL WV MAY TEND TO WEAKEN SOME AS IT MOVES INTO THIS WEAKER INSTABILITY AREA AND OUT OF WW 146. WE WILL MONITOR TRENDS FOR THE NEED FOR AN ADDITIONAL WATCH IN THIS AREA AS WELL. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842 WWWW From Mcd at goshenarc.org Mon Apr 3 23:34:54 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 19:34:54 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032333 SWOMCD SPC MCD 032333 SCZ000-NCZ000-GAZ000-040000- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 0633 PM CDT MON APR 03 2006 AREAS AFFECTED...WRN AND CENTRAL CAROLINAS CONCERNING...TORNADO WATCH 147... VALID 032333Z - 040000Z STRONGER STORMS CONTINUE MOVING EWD OUT OF ERN PORTIONS OF WW 147 INTO WW 148...WHILE CONVECTION FURTHER W INTO WW 147 CONTINUES TO WEAKEN. THEREFORE...WW 147 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 04/00Z. SEVERE THREAT ACROSS WW 147 CONTINUES TO DIMINISH...AS WLY SURFACE WINDS ARE ADVECTING MUCH DRIER/MORE STABLE BOUNDARY LAYER EWD ACROSS WRN PORTIONS OF THE NC/SC. MOST UNSTABLE AIRMASS REMAINS ACROSS THE ERN CAROLINAS...WHERE WW 148 IS NOW IN EFFECT. THOUGH A FEW SEVERE STORMS MAY PERSIST FOR A COUPLE OF HOURS ACROSS SERN SC -- S OF WW 148 AND SE OF WW 147...AREA OF THREAT REMAINS SMALL. THEREFORE...LIMITED TEMPORAL AND SPATIAL EXTENT OF THREAT AREA PRECLUDES THE NEED FOR A NEW WW. ..GOSS.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...ILM...RNK...CAE...GSP...FFC... 33638252 35938128 36098053 34307982 WWWW From Mcd at goshenarc.org Tue Apr 4 00:21:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 20:21:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040020 SWOMCD SPC MCD 040019 TXZ000-040215- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 0719 PM CDT MON APR 03 2006 AREAS AFFECTED...SCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 040019Z - 040215Z TOWERING CU WAS DEVELOPING ALONG A STATIONARY BOUNDARY OVER SCENTRAL TX FROM THE DRT AREA EWD TO NEAR SAT AND AUS AREA. MODERATE-STG INSTABILITY WILL AID IN POTENTIAL FOR ISOLATED SVR WIND/HAIL... DESPITE MARGINAL VERTICAL WIND SHEAR. LATEST SFC ANALYSIS INDICATES A STATIONARY FRONT EXTENDING FROM NEAR DRT EWD TO JUST SOUTH OF KERRVILLE EWD TO BASTROP COUNTY. MODERATE INSTABILITY WITH MLCAPES AROUND 2000 J/KG EXISTED ALONG AND SOUTH OF THIS BOUNDARY. ALTHOUGH CONVERGENCE IS RELATIVELY WEAK ALONG THE BOUNDARY...CONTINUED DAYTIME HEATING SHOULD AID IN AT LEAST AN ISOLATED TSTM DEVELOPMENT. GIVEN THE DEGREE OF INSTABILITY AND STEEP LOW-MID LVL LAPSE RATES...THERE WILL BE SOME POTENTIAL FOR ISOLATED SVR HAIL/WIND AS STORMS MOVE SEWD AROUND 15 KTS. RELATIVELY WEAK MID LEVEL WINDS WILL BE SOMEWHAT OFFSET BY ELY LOW LEVEL WINDS...ENHANCING VERTICAL SHEAR. HOWEVER...SHEAR SHOULD REMAIN LOW ENOUGH THAT AN ORGANIZED SVR THREAT IS NOT ANTICIPATED. ..CROSBIE.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842 WWWW From Mcd at goshenarc.org Tue Apr 4 01:17:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 21:17:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040116 SWOMCD SPC MCD 040116 VAZ000-DEZ000-MDZ000-PAZ000-NCZ000-SCZ000-040245- MESOSCALE DISCUSSION 0424 NWS STORM PREDICTION CENTER NORMAN OK 0816 PM CDT MON APR 03 2006 AREAS AFFECTED...ERN MD/ERN VA/ERN NC/NERN SC CONCERNING...TORNADO WATCH 148... VALID 040116Z - 040245Z LINE OF STRONG/SEVERE STORMS CONTINUES MOVING EWD ACROSS WW. LATEST RADAR IMAGERY SHOWS LINE OF STRONG TO LOCALLY SEVERE THUNDERSTORMS EXTENDING FROM THE DELMARVA REGION SSWWD INTO ERN NC. MEANWHILE...A SECOND CLUSTER OF STORMS CONTINUES MOVING ACROSS COASTAL PORTIONS OF NC AND THE NERN SC COAST. STORMS OVER E CENTRAL AND NERN VA CONTINUE TO MOVE EWD INTO COOLER/MORE STABLE BOUNDARY LAYER...AS SELY SURFACE WINDS CONTINUE TO ADVECT ATLANTIC AIR INLAND. THEREFORE...EXPECT STORMS TO WEAKEN WITH TIME...WITH ONLY A MARGINAL HAIL THREAT LIKELY TO LINGER AS STORMS MOVE OUT OF THE NERN CORNER OF WW 148 AND EVENTUALLY OFF THE NJ/DE COASTS. FURTHER S INTO SERN VA/ERN NC/NERN SC...POCKETS OF MODERATE INSTABILITY REMAIN. WITH STRONGEST MID-LEVEL FLOW ACROSS THE ERN CAROLINAS ATTM...DEEP-LAYER SHEAR REMAINS SUFFICIENT FOR LOCALLY SEVERE/SUPERCELL STORMS. THEREFORE...EXPECT SEVERE THREAT TO LINGER FOR A COUPLE MORE HOURS -- PARTICULARLY ACROSS ERN NC WHERE STORMS SHOULD REMAIN ONSHORE THE LONGEST. ..GOSS.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...MHX...CTP...LWX...RAH...ILM...CAE... 33637997 35267983 36727737 38267643 39737667 39737562 33677649 WWWW From Mcd at goshenarc.org Tue Apr 4 03:02:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 23:02:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040302 SWOMCD SPC MCD 040301 NCZ000-SCZ000-040400- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 1001 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR NERN SC/SERN NC CONCERNING...TORNADO WATCH 148... VALID 040301Z - 040400Z SEVERE THREAT CONTINUES TO DECREASE. WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 04/04Z. LATEST RADAR LOOP SHOWS MOST CONVECTION WEAKENING/MOVING OFFSHORE ATTM. GREATEST INSTABILITY -- AND THUS LINGERING SEVERE THREAT -- IS INDICATED ACROSS FAR NERN SC AND SERN NC...WHERE STRONGEST STORMS ARE INDICATED. THOUGH LIMITED/LOCAL SEVERE THREAT MAY PERSIST FOR THE NEXT 1-2 HOURS ACROSS A FEW COUNTIES IN THIS AREA...STORMS SHOULD CONTINUE TO GENERALLY WEAKEN AND MOVE OFFSHORE WITH TIME. ..GOSS.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...ILM... 33667930 34567810 35287761 35137630 33677649 WWWW From Mcd at goshenarc.org Tue Apr 4 16:43:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 12:43:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 041642 SWOMCD SPC MCD 041642 CAZ000-041845- MESOSCALE DISCUSSION 0426 NWS STORM PREDICTION CENTER NORMAN OK 1142 AM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL CA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 041642Z - 041845Z THUNDERSTORM INITIATION WILL BE LIKELY ACROSS THE SAN JOAQUIN VALLEY AND SCNTRL COAST THIS AFTERNOON. THE STRONGER STORMS WILL HAVE A POTENTIAL FOR LARGE HAIL AND A WW MAY BECOME NECESSARY. LATEST SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING FROM THE SANTA BARBARA VICINITY NWD ACROSS THE SAN JOAQUIN VALLEY WITH DEWPOINTS IN THE MID 50S F. PARTIAL CLEARING IS EVIDENT ON VISIBLE IMAGERY OVER THE VALLEY WHERE TEMPS HAVE WARMED TO NEAR 60 F. ADDITIONAL DESTABILIZATION COMBINED WITH STRONG VERTICAL SHEAR WILL BE FAVORABLE FOR ROTATING STORMS. COLD AIR ALOFT ASSOCIATED WITH AN APPROACHING VIGOROUS UPPER-LEVEL TROUGH WILL CONTINUE TO STEEPEN LAPSE RATES OVER CNTRL CA THIS AFTERNOON WITH THE THREAT FOR LARGE HAIL GRADUALLY INCREASING. ISOLATED WIND DAMAGE AND/OR BRIEF TORNADOES MAY ALSO BECOME POSSIBLE AS SFC HEATING FURTHER DESTABILIZES THE AIR MASS ..BROYLES.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HNX...LOX...STO...MTR... 35631972 35602061 35702115 35872147 36342152 37242145 38062116 38122031 37881956 37201942 WWWW From Mcd at goshenarc.org Tue Apr 4 18:32:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 14:32:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 041831 SWOMCD SPC MCD 041831 FLZ000-042030- MESOSCALE DISCUSSION 0427 NWS STORM PREDICTION CENTER NORMAN OK 0131 PM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 041831Z - 042030Z SCATTERED THUNDERSTORMS SHOULD DEVELOP THIS AFTERNOON ALONG A SFC BOUNDARY ACROSS CNTRL FL. THE STRONGER CELLS WILL HAVE A POTENTIAL FOR HAIL AND DAMAGING WIND GUSTS. LATEST SFC ANALYSIS SHOWS A SLOW MOVING COLD FRONT EXTENDING EWD FROM TAMPA BAY ACROSS THE CNTRL PENINSULA. SFC DEWPOINTS ALONG AND SOUTH OF THE BOUNDARY ARE IN THE MID 60S F AND MODERATE INSTABILITY HAS DEVELOPED DUE TO MOST CLEAR SKIES. VISIBLE IMAGERY SHOWS A SEA BREEZE FRONT MOVING INLAND ACROSS ERN FL AND NEW STORMS SHOULD INITIATE ALONG THE SEA BREEZE-COLD FRONTAL BOUNDARY INTERSECTION AS TEMPS CONTINUE TO WARM AND LOW-LEVEL CONVERGENCE INCREASES. FORECAST SOUNDINGS ACROSS THE CNTRL FL PENINSULA THIS AFTERNOON SHOW A WEAK TO MODERATELY SHEARED ENVIRONMENT WITH RELATIVELY STEEP LAPSE RATES. THIS SUGGESTS SEVERE MULTICELL STORMS WOULD BE FAVORED WITH A POTENTIAL FOR HAIL. IN ADDITION...STEEPENING LOW-LEVEL LAPSE RATES THIS AFTERNOON SHOULD RESULT IN A POTENTIAL FOR DAMAGING WIND GUSTS WITH THE STRONGER CELLS. ..BROYLES.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...TBW... 27248087 27018194 27128227 27528245 27868231 28138137 28138087 27488058 WWWW From Mcd at goshenarc.org Tue Apr 4 23:10:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 19:10:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 042309 SWOMCD SPC MCD 042309 UTZ000-IDZ000-NVZ000-050115- MESOSCALE DISCUSSION 0428 NWS STORM PREDICTION CENTER NORMAN OK 0609 PM CDT TUE APR 04 2006 AREAS AFFECTED...NERN NV/SRN ID CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 042309Z - 050115Z ...ISOLD SVR TSTMS WILL CONTINUE TO DEVELOP ACROSS PORTIONS OF THE SNAKE RIVER VALLEY WITH POTENTIAL FOR DAMAGING WINDS AND HAIL... LATEST RADAR LOOPS SHOW SEVERAL STORMS HAVE DEVELOPED NORTHEAST OF ELKO AND SOUTHEAST OF BOISE. BOUNDARY LAYER TEMPS HAVE INCREASED INTO THE LOWER 60S...WHICH HAS CONTRIBUTED TO MLCAPE VALUES NEAR 1000 J/KG. LARGE SCALE ASCENT HAS BEEN INCREASING ACROSS THE ENTIRE REGION ASSOCIATED WITH DIFFLUENT UPPER LEVEL TROUGH. WIND FIELDS ALOFT ARE VERY STRONG...WITH VAD WIND DATA SHOWING 40 KT WITHIN THE LOWEST 1KM AGL AT ELKO. DEEP LAYER SHEAR PROFILES /IN EXCESS OF 50KT/ WILL SUPPORT SUPERCELL STRUCTURES...AND RECENT RADAR DATA FROM BOISE HAS BEEN INDICATING LOW LEVEL ROTATION WITH STORM NEARING MOUNTAIN HOME ID. IN ADDITION TO THE THREAT OF LARGE HAIL...VERY STRONG WIND GUSTS ARE LIKELY. ..TAYLOR.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SLC...PIH...BOI...LKN...REV... 39141664 39861772 43061611 43141510 42841315 42261316 40181479 39211572 WWWW From Mcd at goshenarc.org Tue Apr 4 23:36:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 19:36:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 042335 SWOMCD SPC MCD 042334 NVZ000-CAZ000-050030- MESOSCALE DISCUSSION 0429 NWS STORM PREDICTION CENTER NORMAN OK 0634 PM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL CA CONCERNING...SEVERE THUNDERSTORM WATCH 149... VALID 042334Z - 050030Z ...ISOLD SVR THREAT WILL CONTINUE EAST OF FRESNO/HANFORD THROUGH 02Z... LATEST RADAR TRENDS ARE BEING MONITORED ACROSS CNTRL CA...WHERE WIND FIELDS REMAIN EXTREMELY STRONG AHEAD OF APPROACHING TROUGH. STORMS HAVE INCREASED OVER THE LAST HOUR OR SO...WHERE AIRMASS HAS BECOME MARGINALLY UNSTABLE. TEMPERATURES AT 500MB ARE AT LEAST MINUS 20 CELSIUS OR BELOW AND THIS IS PROMOTING STEEP LAPSE RATES. SEVERE THREAT WILL LIKELY PERSIST BEYOND THE EXPIRATION OF WW 149 AND THE WATCH MAY NEED TO BE LOCALLY EXTENDED. SVR THREAT WILL MAINLY EXIST FOR LARGE HAIL. WINDS VEER TO WLY BEHIND CONVECTIVE LINE WHICH EXTENDS FROM NE OF FAT TO HJO...SO PRIMARY THREAT APPEARS TO REMAIN OVER PARTS OF MADERA/FRESNO/TULARE COUNTIES. ..TAYLOR.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...VEF...REV...HNX...STO... 35571825 35601901 36872002 37882038 38551976 38421872 36941704 36141715 WWWW From Mcd at goshenarc.org Wed Apr 5 16:55:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 12:55:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 051654 SWOMCD SPC MCD 051653 WYZ000-COZ000-NMZ000-AZZ000-UTZ000-IDZ000-051900- MESOSCALE DISCUSSION 0430 NWS STORM PREDICTION CENTER NORMAN OK 1153 AM CDT WED APR 05 2006 AREAS AFFECTED...ERN UT/WRN CO AND SW WY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 051653Z - 051900Z THUNDERSTORM DEVELOPMENT WILL CONTINUE THROUGH EARLY AFTERNOON ACROSS WRN CO...ERN UT AND SWRN WY. THE MORE INTENSE STORMS WILL HAVE A POTENTIAL FOR HAIL AND ISOLATED WIND DAMAGE. A WW WILL LIKELY BECOME NECESSARY BY THIS AFTERNOON ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN IMPRESSIVE WEST COAST UPPER-LEVEL TROUGH WITH A DRY SLOT AND BAND OF STRONG LARGE-SCALE ASCENT DRIFTING ENEWD ACROSS THE REGION. A LINE OF STORMS IS ONGOING ALONG THE LEADING EDGE OF ASCENT AND ADDITIONAL STORMS SHOULD DEVELOP ACROSS ERN UT OVER THE NEXT HOUR AS SFC TEMPS WARM TO NEAR 70 F AND ASCENT INCREASES IN THE NOSE OF A 100 KT MID-LEVEL JET. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW VERY STEEP MID-LEVEL LAPSE RATES AND STRONG VERTICAL SHEAR SUGGESTING SUPERCELLS WITH HAIL POTENTIAL WILL INCREASE. IN ADDITION...SFC TEMP-DEWPOINT DEPRESSIONS WILL EXCEED 30 DEGREES F ENHANCING THE WIND DAMAGE POTENTIAL WITH THE STRONGER CELLS. ..BROYLES.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PUB...CYS...ABQ...RIW...GJT...FGZ...SLC...PIH... 36770798 36740897 37400978 38851007 40951077 41831106 42231108 42741046 42950907 42490809 41200763 40080736 38740711 38670697 37530713 37060743 WWWW From Mcd at goshenarc.org Wed Apr 5 22:00:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 18:00:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 052159 SWOMCD SPC MCD 052159 MTZ000-WYZ000-052330- MESOSCALE DISCUSSION 0431 NWS STORM PREDICTION CENTER NORMAN OK 0459 PM CDT WED APR 05 2006 AREAS AFFECTED...NRN WY INTO S-CNTRL AND SERN MT CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 052159Z - 052330Z POTENTIAL FOR LOCALLY STRONG WIND GUSTS AND PERHAPS ISOLATED LARGE HAIL WILL INCREASE ACROSS AREA LATE THIS AFTERNOON INTO EVENING. CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE WW. LATEST MESOANALYSIS INDICATED LOW PRESSURE S OF LND AND SW COD WITH ATTENDANT WARM FRONT EXTENDING ENEWD ACROSS FAR SERN MT AND THEN INTO CNTRL SD. TRAILING COLD FRONT THEN EXTENDED SWD FROM THESE LOW PRESSURE CENTERS INTO WRN CO. WELL-DEFINED RISE-FALL COUPLET FROM N-CNTRL WY INTO ERN UT SUGGESTS THAT THIS LOW PRESSURE WILL CONTINUE TO DEVELOP NEWD INTO SRN MT THIS EVENING. MODIFICATION OF 18Z RIW SOUNDING FOR CURRENT SURFACE OBSERVATIONS ACROSS N-CNTRL WY INDICATES STEEP LOW TO MID-LEVEL LAPSE RATES AND SBCAPES OF AROUND 1000 J/KG. GIVEN A DEEP AND WELL-MIXED BOUNDARY-LAYER COUPLED WITH DCAPES OF 1000-1300 J/KG...POTENTIAL WILL EXIST FOR LOCALLY STRONG DOWNDRAFTS WITH MOST INTENSE STORMS. MOREOVER...40-50 KTS OF DEEP-LAYER SHEAR ALSO SUGGESTS A THREAT OF MARGINAL SUPERCELL STRUCTURES CAPABLE OF ISOLATED LARGE HAIL. STRENGTHENING UPPER DIVERGENCE AHEAD OF EVOLVING UPPER LOW OVER THE GREAT BASIN SHOULD SUPPORT AN INCREASE IN CONVECTIVE COVERAGE LATE THIS AFTERNOON INTO EVENING ACROSS N-CNTRL/NERN WY INTO S-CNTRL AND SERN MT. PRIMARY QUESTION IS WHETHER THIS STRONGER FORCING FOR ASCENT WILL SUFFICIENTLY OFFSET A COOLING BOUNDARY-LAYER AFTER 23-00Z...SUSTAINING A SEVERE THREAT THROUGH THE EVENING. ..MEAD.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...UNR...CYS...BYZ...RIW... 43190960 44161028 45750960 46490779 46300568 44980442 43590459 42890561 42560709 WWWW From Mcd at goshenarc.org Wed Apr 5 22:42:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 18:42:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 052242 SWOMCD SPC MCD 052241 WYZ000-COZ000-NMZ000-AZZ000-UTZ000-IDZ000-052345- MESOSCALE DISCUSSION 0432 NWS STORM PREDICTION CENTER NORMAN OK 0541 PM CDT WED APR 05 2006 AREAS AFFECTED...SWRN WY / ERN UT / WRN CO CONCERNING...SEVERE THUNDERSTORM WATCH 151... VALID 052241Z - 052345Z POTENTIAL FOR LOCALLY STRONG WIND GUSTS WILL LIKELY CONTINUE BEYOND 23Z...HOWEVER AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. CLUSTERS OF TSTMS ARE ONGOING AS OF 2225Z FROM N-CNTRL NM NWD THROUGH PORTIONS OF WRN AND CNTRL CO INTO WRN AND CNTRL WY WITHIN ZONE OF STRONG LARGE-SCALE FORCING FOR ASCENT ASSOCIATED WITH UPPER LOW EVOLVING OVER THE GREAT BASIN. REGIONAL VWPS INDICATE LARGELY UNIDIRECTIONAL WIND PROFILES WITH RELATIVELY STRONG VERTICAL SPEED SHEAR...SUPPORTIVE OF ORGANIZED SEVERE TSTMS. HOWEVER...VISIBLE SATELLITE AND SURFACE OBSERVATIONS INDICATE THAT CONSIDERABLE CLOUDS AND PRECIPITATION HAVE RESULTED IN COOLING OF PRE-FRONTAL BOUNDARY-LAYER ACROSS WRN INTO CNTRL CO WHICH IS EFFECTIVELY LIMITING THE DEGREE OF INSTABILITY. THROUGH 23-01Z...IT APPEARS THE GREATEST THREAT OF LOCALLY STRONG WIND GUSTS AND/OR MARGINALLY SEVERE HAIL WILL EXIST ACROSS NRN PORTIONS OF WW AREA INTO N-CNTRL WY/S-CNTRL AND SERN MT WHERE INTENSIFYING LARGE-SCALE FORCING WILL BECOME CO-LOCATED WITH A ZONE OF WEAK TO MODERATE INSTABILITY. ELSEWHERE...AN ISOLATED SEVERE WEATHER THREAT MAY EXIST BEYOND 23Z...HOWEVER IT APPEARS THAT THE TEMPORAL DURATION OF THIS THREAT WILL BE TOO LIMITED TO WARRANT THE ISSUANCE OF AN ADDITIONAL WW. ..MEAD.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PUB...BOU...CYS...ABQ...RIW...GJT...FGZ...SLC...PIH... 43521113 43560949 42540830 42470568 36600617 36741098 WWWW From Mcd at goshenarc.org Thu Apr 6 03:38:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 23:38:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 060337 SWOMCD SPC MCD 060336 MOZ000-ILZ000-IAZ000-060500- MESOSCALE DISCUSSION 0433 NWS STORM PREDICTION CENTER NORMAN OK 1036 PM CDT WED APR 05 2006 AREAS AFFECTED...E-CNTRL MO NWD INTO CNTRL AND SRN IA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 060336Z - 060500Z ELEVATED TSTM COVERAGE IS EXPECTED TO INCREASE ACROSS DISCUSSION AREA OVERNIGHT. SEVERE HAIL WILL BE POSSIBLE WITH THE MOST INTENSE STORMS AND CONVECTIVE TRENDS WILL BE MONITORED FOR A WW ISSUANCE. AS OF 0320Z...REGIONAL RADAR IMAGERY SHOWED A PERSISTENT CLUSTER OF ELEVATED STORMS FROM WASHINGTON COUNTY NWWD INTO CALLAWAY COUNTY MO WITH NICKEL TO GOLFBALL-SIZED HAIL RECENTLY REPORTED. ANOTHER CLUSTER OF ELEVATED TSTMS HAS PERSISTED FROM NEAR CID SEWD TO E OF UIN. FINALLY...IR SATELLITE DATA SHOW A BAND OF CLOUD ENHANCEMENT FROM THE ONGOING...E-CNTRL MO ACTIVITY NWWD TO NEAR OMA. REGIONAL VWP/PROFILER DATA AND SHORT-TERM MODEL GUIDANCE SUGGEST THAT THIS ACTIVITY IS OCCURRING ALONG AN INTENSIFYING SLY/SWLY LLJ ON THE ERN OR NERN EDGE OF CAP WHICH IS IN PLACE OVER THE CNTRL PLAINS /PER 00Z SOUNDING OBSERVATIONS/. HERE...INCREASING MOISTURE IN THE 850-800 MB LAYER BENEATH STEEP MID-LEVEL LAPSE RATES ARE RESULTING IN AIR MASS DESTABILIZATION FOR ELEVATED PARCELS WITH MUCAPES OF 1000-1500 J/KG. AN INCREASE IN STORM COVERAGE IS ANTICIPATED OVERNIGHT OWING TO FURTHER STRENGTHENING OF LLJ AND RESULTANT FORCING VIA WAA AND ISENTROPIC ASCENT. GIVEN THE MODERATE INSTABILITY AND SHEAR THROUGH THE CLOUD-BEARING LAYER...SEVERE HAIL WILL BE POSSIBLE WITH THE STRONGEST STORMS. ..MEAD.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...DMX...EAX...OAX... 38479132 38539224 40279512 41519592 41969536 42129316 41839182 40539070 39079055 38699088 WWWW From Mcd at goshenarc.org Thu Apr 6 06:22:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 02:22:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 060621 SWOMCD SPC MCD 060620 SDZ000-NEZ000-060745- MESOSCALE DISCUSSION 0434 NWS STORM PREDICTION CENTER NORMAN OK 0120 AM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL/SRN SD AND EXTREME NRN NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 060620Z - 060745Z TSTMS OVER SWRN SD WILL LIKELY EXPAND ESEWD INTO EXTREME NRN NEB AND ACROSS A LARGE PART OF SRN/CNTRL SD EARLY THIS MORNING. STRONGER STORMS WILL PRODUCE LARGE HAIL AND A SEVERE THUNDERSTORM WATCH MAY BE REQUIRED. H5 JET OF 70+ KTS ALONG ERN PERIPHERY OF THE WY UPPER LOW WAS NOSING NWD INTO WRN NEB...PLACING A STRONG DIFFLUENT/DIVERGENT FLOW REGIME ACROSS THE CNTRL/NRN HIGH PLAINS EARLY THIS MORNING. CORRESPONDING SLY LLJ OF AROUND 50 KTS WAS IMPINGING ON AN E-W ORIENTED BAROCLINIC ZONE SITUATED ACROSS THE NE/SD BORDER. RESULTING DEEP UVV WAS ALREADY SUPPORTING TSTMS ACROSS SWRN SD. PRIND THAT TSTMS WILL DEVELOP ESEWD ALONG/N OF THE AFOREMENTIONED BAROCLINIC ZONE INTO EXTREME NRN NEB AND CNTRL/SRN SD THE NEXT FEW HOURS. THOUGH EFFECTIVE VERTICAL SHEAR IS GENERALLY LESS THAN 35 KTS...LAPSE RATES WERE QUITE STEEP. THUS...AS TSTMS DEVELOP...UPDRAFTS WILL BE STRONG WITH LARGE HAIL PRODUCTION QUITE LIKELY. AS THE NUMBER OF STORMS INCREASE...COMPETITION OF UPDRAFTS MAY TEND TO TEMPER THE SEVERITY OF THE STORMS LATER IN THE MORNING. BUT...THERE APPEARS THAT THERE WILL BE A FEW HOURS OF LARGE HAIL POTENTIAL AND A WW MAY BE REQUIRED. ..RACY.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FSD...OAX...ABR...LBF...UNR...CYS... 44870270 44689987 44379712 44039719 42089784 42319911 43020306 WWWW From Mcd at goshenarc.org Thu Apr 6 11:02:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 07:02:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061101 SWOMCD SPC MCD 061101 MOZ000-KSZ000-IAZ000-NEZ000-061300- MESOSCALE DISCUSSION 0435 NWS STORM PREDICTION CENTER NORMAN OK 0601 AM CDT THU APR 06 2006 AREAS AFFECTED...SERN NEB...NERN KS...NWRN MO CONCERNING...OUTLOOK UPGRADE VALID 061101Z - 061300Z AFTER COLLABORATION WITH THE TOP/OAX/EAX WEATHER FORECAST OFFICES... THE STORM PREDICTION CENTER IS EXPECTED TO UPGRADE SERN NEB...NERN KS AND NWRN MO TO A CATEGORICAL HIGH RISK AT 13Z. H5 12-HR HEIGHT FALLS OF 210 METERS WILL SPREAD ENEWD ACROSS THE CNTRL PLAINS THIS AFTN. TSTMS ARE EXPECTED TO DEVELOP BY EARLY AFTN ALONG THE DRYLINE/SFC LOW FROM SCNTRL NEB INTO CNTRL KS AS INHIBITION IS ERODED. STORMS SHOULD QUICKLY ORGANIZE INTO SUPERCELLS GIVEN STRONG VERTICAL SHEAR PROFILES /H5 FLOW OF 105 KTS OVER OKLA...WITH AOA 60 KTS INTO ERN KS/. THE 2-8KM SHEAR VECTORS REMAIN SUFFICIENTLY NORMAL TO THE INITIATING BOUNDARY TO SUPPORT DISCRETE CELLS...THOUGH ACTIVITY WILL TEND TO EVOLVE INTO A MIXED MODE OF LEWPS/BOWS WITH TIME. NONETHELESS...BACKED SELY LOW-LEVEL FLOW E/NE OF THE SFC LOW/WARM FRONT WILL BE FAVORABLE FOR TORNADOES...SOME STRONG...AS THE STORMS MOVE ENEWD AT 30-40 KTS ACROSS NERN KS...SERN NEB AND NWRN MO. VERY LARGE HAIL CAN ALSO BE EXPECTED GIVEN STEEP MID-LEVEL LAPSE RATES AND 2000-2500 J/KG MLCAPE. ..RACY/EVANS.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EAX...OAX...TOP... 38339578 39589716 40779702 40919601 40319468 39399408 38529421 38249500 WWWW From Mcd at goshenarc.org Thu Apr 6 16:04:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 12:04:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061603 SWOMCD SPC MCD 061603 ARZ000-MOZ000-LAZ000-TXZ000-OKZ000-KSZ000-061800- MESOSCALE DISCUSSION 0436 NWS STORM PREDICTION CENTER NORMAN OK 1103 AM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK/SW MO/WRN AR/ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061603Z - 061800Z ...POTENTIAL FOR ISOLD SEVERE STORMS THROUGH EARLY AFTN FROM ECNTRL OK SWD TO PARTS OF ERN TX...AND EWD INTO AR... ELEVATED TSTMS CONTINUE TO INTENSIFY ACROSS ECNTRL OK...WITH LATEST TULSA OK RADAR IMAGERY SUGGESTING INTENSE MID LEVEL CORES. LATEST WV IMAGERY INDICATES AN IMPULSE NOW MOVING ACROSS CNTRL KS/OK...AND THIS IS LIKELY AGITATING THE STORMS. IN ADDITION...LARGE SCALE ASCENT IS BEING AUGMENTED BY DIFFLUENT FLOW ALOFT. 12Z SOUNDING FROM NORMAN OK SHOWED AROUND 1700 J/KG MUCAPE...WITH SLIGHTLY STRONGER CAPE EVIDENT ON THE 12Z SPRINGFIELD MO SOUNDING. SPECIAL 15Z SOUNDING FROM SPRINGFIELD SUGGESTS STORMS ARE ROOTED NEAR 700MB. STORMS ARE FORMING WITHIN AN ENVIRONMENT OF STRONG DEEP LAYER SHEAR /AROUND 40 KT/ AND MODERATE ELEVATED INSTABILITY. STORMS ARE EXPECTED TO CONTINUE DEVELOPING SWD...WITH THE MAIN THREAT FROM LARGE HAIL. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...HGX...ICT...FWD...OUN... 33039395 30769505 30649667 33689707 36159641 37239475 37299338 36099266 33919325 WWWW From Mcd at goshenarc.org Thu Apr 6 16:20:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 12:20:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061619 SWOMCD SPC MCD 061619 INZ000-KYZ000-ILZ000-MOZ000-IAZ000-061715- MESOSCALE DISCUSSION 0437 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 06 2006 AREAS AFFECTED...SERN IA/ERN MO/MUCH OF CENTRAL-SRN IL/FAR SWRN IND/FAR WRN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061619Z - 061715Z ELEVATED STORMS WILL CONTINUE TO DEVELOP INTO THE AFTERNOON FROM SERN IA SEWD THROUGH ERN MO/MUCH OF CENTRAL-SRN IL INTO FAR SWRN IND AND FAR WRN KY. LATE MORNING SURFACE ANALYSIS SHOWED A DEEPENING SURFACE LOW LOCATED OVER ERN NEB...WITH A WARM FRONT EXTENDING SEWD THROUGH SWRN IA/NRN TO ERN MO AROUND STL..AND THEN EWD ACROSS SRN IL INTO FAR SRN IND. A SURFACE TROUGH EXTENDED SWD FROM CENTRAL MO /BOONE COUNTY/ INTO NRN AR. LARGE SCALE ASCENT DOWNSTREAM OF SHORT WAVE TROUGH LOCATED OVER CENTRAL KS/OK WILL SUPPORT ADDITIONAL ELEVATED STORMS TO THE NORTH OF THE WARM FRONT AND EAST OF THE SURFACE TROUGH...AS THIS MID LEVEL IMPULSE TRACKS NEWD TOWARD THE LOWER MO/MID MS VALLEYS TODAY. SPECIAL 15Z SOUNDING AT SGF CONTINUED TO INDICATE A STEEP LAPSE RATE ENVIRONMENT OVER MO...BUT THE AIR MASS REMAINS CAPPED. 15Z RUC SOUNDINGS ACROSS THE DISCUSSION AREA SUGGEST STORMS ARE ROOTED AROUND 850 MB WITH CLOUD LAYER SHEAR SUPPORTIVE OF ELEVATED ROTATING STORMS. WEAK INSTABILITY SHOULD LIMIT THE COVERAGE OF STRONGER CORES. HOWEVER...STEEP LAPSE RATES INDICATED A THREAT FOR ISOLATED HAIL...LOCALLY EXCEEDING SEVERE LEVELS AT TIMES. ..PETERS.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...ILX...LSX...DVN...DMX...EAX... 40639240 41659279 41989165 41799039 40608889 39848761 38408698 36838743 36628864 36728976 37889107 39269164 WWWW From Mcd at goshenarc.org Thu Apr 6 17:14:00 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 13:14:00 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061712 SWOMCD SPC MCD 061712 NEZ000-KSZ000-061915- MESOSCALE DISCUSSION 0438 NWS STORM PREDICTION CENTER NORMAN OK 1212 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH ERN NEB THROUGH MUCH OF CNTRL KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061712Z - 061915Z THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS PORTIONS OF CNTRL NEB SWD THROUGH CNTRL KS BETWEEN 19 AND 21Z. ORGANIZED STORM STRUCTURES APPEAR LIKELY INCLUDING SUPERCELLS AND LINE SEGMENTS. THREATS WILL INCLUDE LARGE HAIL AND A FEW TORNADOES. ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE. A TORNADO WATCH WILL LIKELY BE NEEDED FOR PORTIONS OF THESE AREAS BY 18Z. EARLY THIS AFTERNOON A SURFACE FRONT EXTENDS FROM A LOW IN E CNTRL NEB SWWD THROUGH W CNTRL KS THEN SWD AS A DRYLINE/PACIFIC FRONT THROUGH WRN OK AND THE ERN PORTION OF WRN TX. WV IMAGERY SHOWS A LOBE OF VORTICITY AND ACCOMPANYING UPPER JET ADVANCING ENEWD THROUGH WRN KS AND WRN NEB. ASCENT AND HEIGHT FALLS ASSOCIATED WITH THIS FEATURE WILL CONTRIBUTE TO SECONDARY CYCLOGENESIS OVER N CNTRL KS THIS AFTERNOON. LATEST SURFACE ANALYSIS ALREADY SHOWS PRESSURE FALLS ACROSS CNTRL THROUGH SWRN KS. AS THE SURFACE LOW DEVELOPS...THE BOUNDARY LAYER FLOW OVER NEB SHOULD BECOME MORE ELY WITH SOME WWD RETREAT OF THE FRONT AND LOW LEVEL MOISTURE. STRONG SURFACE HEATING...ASCENT...AND EWD ADVANCE COLDER AIR ALOFT AND STEEPER LAPSE RATES WILL CONTINUE TO DESTABILIZE THE ATMOSPHERE FROM CNTRL THROUGH ERN NEB SWD THROUGH CNTRL KS WITH MLCAPE FROM 1500 TO 2000 J/KG LIKELY LATER THIS AFTERNOON. MID LEVEL CLOUDS DEVELOPING ACROSS PORTIONS OF WRN AND CNTRL KS ARE PROBABLY INDICATIVE OF THE LEADING EDGE OF ASCENT SPREADING EWD. AS THE ATMOSPHERE CONTINUES TO DESTABILIZE AND HEIGHT FALLS/FORCING FOR ASCENT SPREAD EWD...STORMS SHOULD DEVELOP IN VICINITY OF FRONT/DRYLINE FROM CNTRL NEB SWD THROUGH CNTRL KS AND SUBSEQUENTLY SPREAD NEWD. DEEP LAYER AND LOW LEVEL SHEAR WILL CONTINUE TO INCREASE AS THE UPPER JET ADVANCES EWD AND AS SECONDARY BRANCH OF THE LOW LEVEL JET INTENSIFIES ACROSS KS/ERN NEB IN RESPONSE TO CYCLOGENESIS. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...TOP...ICT...GID...LBF...DDC...GLD... 41229639 39119663 37159726 37339891 39319945 40499975 42000019 42469914 42259744 WWWW From Mcd at goshenarc.org Thu Apr 6 17:52:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 13:52:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061751 SWOMCD SPC MCD 061751 OKZ000-061945- MESOSCALE DISCUSSION 0439 NWS STORM PREDICTION CENTER NORMAN OK 1251 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH PARTS OF NERN OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061751Z - 061945Z N CNTRL THROUGH CNTRL OK ARE BEING MONITORED FOR POSSIBLE THUNDERSTORM INITIATION BETWEEN 18Z AND 19Z. PRIMARY THREATS WILL BE SUPERCELLS WITH LARGE HAIL AND ISOLATED TORNADOES. THIS AREA IS BEING MONITORED FOR A POSSIBLE TORNADO WATCH. EARLY THIS AFTERNOON A SURFACE FRONT EXTENDS FROM CNTRL KS SSWWD THROUGH WRN OK. A DRYLINE EXTENDS FROM NWRN TX NWD THROUGH W CNTRL OK AND INTERSECTS THE FRONT IN S CNTRL KS. STRONG SURFACE HEATING AND STEEP LAPSE RATES ARE PROMOTING DESTABILIZATION WITHIN THE WARM SECTOR WHERE DEWPOINTS ARE IN THE LOWER 60S. LATEST OBJECTIVE ANALYSIS ALREADY SHOW AN AXIS OF MLCAPE ON THE ORDER OF 1500 TO 2000 J/KG ACROSS W CNTRL OK IN ADVANCE OF THE DRYLINE. PRESSURE FALLS INDICATIVE OF STRONG FORCING FOR ASCENT ASSOCIATED WITH ENEWD ADVANCING MID LEVEL JET ARE DEVELOPING ACROSS WRN AND W CNTRL KS. THIS ZONE OF FALLS WILL CONTINUE TO SPREAD EWD WITH SURFACE CYCLOGENESIS EXPECTED ACROSS CNTRL KS NEXT FEW HOURS. AS THE LOW DEEPENS...CONVERGENCE WILL INCREASE AND THE DRYLINE/COLD FRONT WILL SHARPEN. THE INCREASING CONVERGENCE AND FORCING FOR ASCENT MAY BE SUFFICIENT FOR THUNDERSTORM INITIATION THIS AFTERNOON INTO PARTS OF CNTRL OK AS THE CAP WEAKENS. LATEST VISIBLE IMAGERY SHOWS BOUNDARY LAYER CUMULUS INCREASING OVER W CNTRL OK JUST W OF OKC. STRENGTHENING LOW TO MID LEVEL WIND FIELDS AND VERTICAL SHEAR WILL SUPPORT SUPERCELL STRUCTURES WITH ANY STORMS THAT DEVELOP. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...OUN... 35099786 35689789 36379788 36949788 36849577 35919599 35119696 WWWW From Mcd at goshenarc.org Thu Apr 6 18:17:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 14:17:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061816 SWOMCD SPC MCD 061815 TXZ000-OKZ000-061945- MESOSCALE DISCUSSION 0440 NWS STORM PREDICTION CENTER NORMAN OK 0115 PM CDT THU APR 06 2006 AREAS AFFECTED...SW OK THROUGH SW TX CONCERNING...CONVECTIVE TRENDS VALID 061815Z - 061945Z ...DRYLINE BEING MONITORED FOR CONVECTIVE TRENDS ACROSS SW OK THROUGH TX... LATEST VISIBLE SATELLITE IMAGERY SHOWS BLOWING DUST WEST OF THE DRYLINE AND BOUNDARY LAYER CUMULUS EAST. EARLY THIS AFTN...THE DRYLINE EXTENDS FROM JUST EAST OF HBR/FDR/SNK/FST. UPPER/MID LEVEL CIRCULATION IS SEEN ON WV LOOPS NOW APPROACHING TX PANHANDLE. ALTHOUGH MOST OF THE LARGE SCALE FORCING WILL BE FOCUSED NORTH OF THE AREA...STRONG SFC HEATING COMBINED WITH LOW LEVEL ASCENT FOCUSED ON THE DRYLINE/PACIFIC FRONT MAY BE ENOUGH TO INITIATE STORMS THIS AFTN. STEEP LAPSE RATES...COMBINED WITH STRONG DEEP LAYER SHEAR AND INCREASING MOISTURE INTO THE WARM SECTOR WILL FAVOR STRONG/SEVERE STORMS...IF AND WHEN DEVELOPMENT OCCURS. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 34709755 32949716 31199785 30259964 30960080 31370067 32439994 32849982 34149889 34429876 34869833 WWWW From Mcd at goshenarc.org Thu Apr 6 19:03:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 15:03:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061902 SWOMCD SPC MCD 061902 MNZ000-SDZ000-NDZ000-062100- MESOSCALE DISCUSSION 0441 NWS STORM PREDICTION CENTER NORMAN OK 0202 PM CDT THU APR 06 2006 AREAS AFFECTED...SD/WRN MN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061902Z - 062100Z ...STRONG AND SEVERE TSTMS WILL CONTINUE ACROSS PORTIONS OF SOUTH DAKOTA NORTH OF WARM FRONT WITH PRIMARILY A THREAT OF LARGE HAIL... MORNING UPPER AIR ANALYSIS AT 850 MB REVEALS BAROCLINIC ZONE ACROSS NRN NEB/SRN SD...AND THIS IS SERVING AS A FOCUS FOR TSTM DEVELOPMENT THIS AFTN. LARGE SCALE ASCENT WILL INCREASE ACROSS THE AREA...SO TSTMS ARE EXPECTED TO CONTINUE THROUGH THE AFTN. LATEST SFC OBSERVATIONAL ANALYSIS SHOWS MUCAPE AROUND 1000-1500 J/KG. STEEP MID LEVEL LAPSE RATES WILL FAVOR STRONG UPDRAFTS...CAPABLE OF LARGE HAIL. IN ADDITION...TRAINING CELLS WILL ALSO POSE A HEAVY RAIN THREAT AS WELL. STORMS MAY HAVE A TENDENCY TO BUILD EWD INTO WRN PORTIONS OF MN LATER THIS AFTN DUE TO INCREASING WAA. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MPX...FGF...FSD...ABR...BIS...UNR... 43819657 43770137 44310263 45640292 46249941 45899568 44269571 WWWW From Mcd at goshenarc.org Thu Apr 6 20:25:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 16:25:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062024 SWOMCD SPC MCD 062024 IAZ000-NEZ000-SDZ000-062230- MESOSCALE DISCUSSION 0442 NWS STORM PREDICTION CENTER NORMAN OK 0324 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH ERN KS...ERN NEB THROUGH WRN IA CONCERNING...TORNADO WATCH 154... VALID 062024Z - 062230Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY TOWARD EVENING FROM ERN KS INTO ERN NEB. THREAT FOR SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE. ISOLATED DAMAGING WIND IS ALSO POSSIBLE. STORMS ARE EXPECTED TO DEVELOP INTO NERN NEB AND WRN IA AFTER 22Z. A WW MAY BE NEEDED FOR THIS AREA WITHIN THE NEXT HOUR OR TWO. THUNDERSTORMS WILL CONTINUE TO INCREASE IN VICINITY OF THE PACIFIC FRONT ACROSS CNTRL KS AS ASCENT ASSOCIATED WITH A STRONG MID LEVEL JET OVERTAKES THE MOIST AXIS. PRESSURE FALLS HAVE INCREASED OVER CNTRL KS IN RESPONSE TO AGEOSTROPHIC FORCING ASSOCIATED WITH THIS FEATURE...AND LEE CYCLONE DEVELOPMENT IS ALSO UNDERWAY OVER N CNTRL KS. PRIMARY LIMITING FACTOR FOR MORE SIGNIFICANT TORNADOES IN THE SHORT TERM HAS BEEN THE SOMEWHAT MARGINAL LOW LEVEL SHEAR AND RELATIVELY HIGH BOUNDARY LAYER-TEMPERATURE DEWPOINT SPREADS. HOWEVER...THE TORNADO THREAT IS EXPECTED TO INCREASE LATER THIS AFTERNOON AND EVENING. THE LOW LEVEL JET WILL STRENGTHEN FROM ERN KS INTO SERN NEB...AND THIS WILL CONTRIBUTE TO AN INCREASE IN LOW LEVEL SHEAR WITHIN THE PRE-FRONTAL WARM SECTOR. SOME DECREASE IN TEMPERATURE-DEWPOINT SPREADS MAY ALSO OCCUR TOWARD EVENING AS THE BOUNDARY LAYER BEGINS TO COOL. ACTIVITY WILL GRADUALLY DEVELOP NEWD THROUGH ERN AND NERN NEB AS WELL AS WRN IA TOWARD EVENING AS FORCING FOR ASCENT SPREADS NEWD. CONVECTIVE MODE WILL INCLUDE SUPERCELLS AS WELL AS LINES WITH LARGE HAIL...ISOLATED TORNADOES AND DAMAGING WIND POSSIBLE. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...FSD...OAX...LBF... 41939463 41409479 41239539 41629610 41739734 41809878 42329901 42829747 42609539 WWWW From Mcd at goshenarc.org Thu Apr 6 20:31:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 16:31:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062030 SWOMCD SPC MCD 062029 ARZ000-MOZ000-062200- MESOSCALE DISCUSSION 0443 NWS STORM PREDICTION CENTER NORMAN OK 0329 PM CDT THU APR 06 2006 AREAS AFFECTED...SCNTRL MO/NCNTRL AR CONCERNING...SEVERE THUNDERSTORM WATCH 153... VALID 062029Z - 062200Z THE MAIN THREAT ACROSS WW 153 IS NOW EAST OF A RUE/BPK LINE. ELEVATED TSTMS HAVE MOVED INTO SCNTRL MO AND NCNTRL AR...WITH THE MOST INTENSE STORM NOW PASSING SE OF FLP. POTENTIAL FOR ADDITIONAL SEVERE WEATHER WILL INCREASE OVER THE NEXT 2-4 HOURS...AS STORMS CONTINUE TO DEVELOP ACROSS NE OK AHEAD OF EWD MOVING SFC BOUNDARY...WHICH EXTENDS ACROSS CNTRL OK. ENVIRONMENT ACROSS NW AR/SW MO HAS BEEN TEMPORARILY STABILIZED DUE TO ELEVATED STORMS WHICH OCCURRED EARLIER AND DESTABILIZATION WILL NEED TO OCCUR. SPECIAL 20Z SOUNDING FROM SPRINGFIELD SHOWS MID LEVEL WARMING HAS OCCURRED ROUGHLY IN THE 600-700MB LAYER. MLCAPE VALUES ARE 1500-2000 J/KG WITHIN INSTABILITY AXIS ACROSS CNTRL OK. LAPSE RATES REMAIN STEEP...AND WIND PROFILES REMAIN FAVORABLE FOR ROTATING STORMS. TO EXPRESS THIS INCREASING SEVERE THREAT ACROSS NE OK/NW AR...THE HIGH RISK HAS BEEN EXTENDED INTO THIS AREA AS OF 20Z. FOR THE REMAINDER OF WW 153 HOWEVER...THE POTENTIAL FOR ELEVATED TSTMS IS DIMINISHING...AND THE WATCH WILL LIKELY EXPIRE AS SCHEDULED AT 23Z. A NEW WATCH WILL BE NEEDED WITHIN A FEW HOURS...POSSIBLY INCLUDING ERN PORTIONS OF TORNADO WATCH 155 AND POINTS FARTHER EAST. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF... 35479151 35079341 35809321 37319268 37639151 37169144 35999136 WWWW From Mcd at goshenarc.org Thu Apr 6 21:22:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 17:22:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062121 SWOMCD SPC MCD 062121 ARZ000-MOZ000-OKZ000-KSZ000-062245- MESOSCALE DISCUSSION 0444 NWS STORM PREDICTION CENTER NORMAN OK 0421 PM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK/WRN AR CONCERNING...TORNADO WATCH 155... VALID 062121Z - 062245Z ...WATCH WILL NEED TO BE ISSUED SHORTLY FOR PORTIONS OF WRN AND NRN AR... TSTMS DEVELOPING MOVING INTO SEBASTIAN CO ARE SFC BASED...AND WILL HAVE AN INCREASING THREAT FOR ROTATING CELLS/TORNADOES. THUS...A TORNADO WATCH WILL NEED TO BE CONSIDERED FOR AR AND MO SOON. FARTHER WEST...TORNADO HAS BEEN REPORTED WITH SUPERCELL ACROSS OSAGE CO AND VAD WIND DATA FROM TULSA CONTINUES TO BE VERY FAVORABLE FOR SUPERCELLS WITH TORNADOES AND LARGE HAIL. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...ICT...OUN... 34149385 34419573 35529671 36869665 37109581 37019491 36399162 34609218 WWWW From Mcd at goshenarc.org Thu Apr 6 21:54:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 17:54:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062153 SWOMCD SPC MCD 062153 MOZ000-IAZ000-OKZ000-KSZ000-NEZ000-062330- MESOSCALE DISCUSSION 0445 NWS STORM PREDICTION CENTER NORMAN OK 0453 PM CDT THU APR 06 2006 AREAS AFFECTED...FAR ERN KS INTO WRN AND CNTRL MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 062153Z - 062330Z POTENTIAL FOR SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES IS EXPECTED TO SPREAD E OF WW 154 BY 23Z AND A NEW TORNADO WATCH WILL BE REQUIRED. AS OF 21Z...MESOANALYSIS INDICATED A RAPIDLY DEEPENING SURFACE LOW OVER S-CNTRL NEB WITH ATTENDANT DRYLINE SURGING ENEWD THROUGH S-CNTRL INTO ERN KS. INTENSE LARGE-SCALE FORCING FOR ASCENT AHEAD OF MID-LEVEL TROUGH AND ASSOCIATED 90-100 KT JET STREAK ARE CONTRIBUTING INCREASING STORM COVERAGE AND INTENSITY FROM MARION COUNTY KS SEWD INTO OSAGE COUNTY OK. STEEP LAPSE RATES COUPLED WITH DIABATIC HEATING AND MODEST BOUNDARY-LAYER DEWPOINTS HAVE CONTRIBUTED TO A MODERATELY UNSTABLE AIR MASS LATE THIS AFTERNOON E OF ONGOING STORMS WITH MLCAPES OF 1000-2000 J/KG. REGIONAL PROFILERS AND VWPS INDICATE DESCENDING MID AND HIGH-LEVEL JET ACROSS INSTABILITY AXIS WITH 55-65 KTS OF DEEP-LAYER SHEAR. MOREOVER...TRENDS IN NEODESHA KS PROFILER SHOW THAT LOW-LEVEL SHEAR HAS STEADILY INCREASED THROUGH THE AFTERNOON. THIS TREND WILL CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON INTO THIS EVENING EWD INTO WRN AND CNTRL MO...SUGGESTING A THREAT FOR LONG-LIVED SUPERCELLS CAPABLE OF A COUPLE STRONG TORNADOES. ..MEAD.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...DMX...EAX...TSA...OAX...TOP...ICT... 39979556 40569467 40589317 39699257 37519211 36699275 36509328 36539433 36669483 WWWW From Mcd at goshenarc.org Fri Apr 7 00:08:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:08:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070007 SWOMCD SPC MCD 070007 TXZ000-OKZ000-070130- MESOSCALE DISCUSSION 0446 NWS STORM PREDICTION CENTER NORMAN OK 0707 PM CDT THU APR 06 2006 AREAS AFFECTED...NCNTRL THROUGH SCNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 156... VALID 070007Z - 070130Z LATEST MESOANALYSIS SHOWS PACIFIC COLD FRONT/DRYLINE EXTENDING FROM LUD/SEP/DRT. AHEAD OF THIS BOUNDARY...SVR TSTM HAS DEVELOPED OVER BURNET COUNTY...WITH A STRONG MID LEVEL CORE AND WITHIN A STRONGLY SHEARED ENVIRONMENT. VISIBLE SATELLITE IMAGERY SHOWS CUMULUS FIELD EXTENDING SWD TO DRT. MODERATE INSTABILITY AXIS SHOWS MLCAPE RANGING FROM 1500-2000 J/KG WITHIN AIRMASS WHERE DEWPOINTS ARE STILL IN THE 60S. WATER VAPOR IMAGERY SUGGESTS STRONGEST FORCING IS FOCUSED FARTHER NORTH...SO ADDITIONAL DEVELOPMENT IS EXPECTED TO BE ISOLD. HOWEVER...ANY SUSTAINED STORMS THAT FORM WILL LIKELY BECOME SEVERE WITH THE MAIN THREAT OF LARGE HAIL OR DAMAGING WINDS. ..TAYLOR.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...HGX...FWD...OUN...EWX...SJT... 30199683 30379848 31379861 33979708 33789457 30709622 WWWW From Mcd at goshenarc.org Fri Apr 7 00:13:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:13:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070012 SWOMCD SPC MCD 070012 IAZ000-MOZ000-KSZ000-NEZ000-070115- MESOSCALE DISCUSSION 0447 NWS STORM PREDICTION CENTER NORMAN OK 0712 PM CDT THU APR 06 2006 AREAS AFFECTED...WRN IA / NWRN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 070012Z - 070115Z THREAT OF LARGE HAIL...LOCALLY DAMAGING WINDS AND PERHAPS A FEW TORNADOES IS EXPECTED TO DEVELOP E OF WW 154 PRIOR 01-02Z. A NEW WW WILL LIKELY BE REQUIRED. AS OF 2355Z...REGIONAL RADAR IMAGERY INDICATED WIDESPREAD TSTMS ONGOING OVER PORTIONS OF ERN NEB...TO THE E OF OCCLUDING SURFACE LOW OVER CNTRL NEB. WITHIN THIS BROADER CONVECTIVE SHIELD...A MESOSCALE CIRCULATION WAS OBSERVED LIFTING NEWD THROUGH SEWARD...LANCASTER...SALINE...JEFFERSON AND GAGE COUNTIES. OMA AND TOP RADAR DATA INDICATE THE PRESENCE OF SMALLER-SCALE SUPERCELL STRUCTURES WITHIN N-S BAND ALONG ERN EDGE OF THIS CIRCULATION AS FAR S AS NEMAHA AND POTTAWATOMIE COUNTIES IN NERN KS. PRESENCE OF DEEP-LAYER FORCING FOR ASCENT IN DIFLUENT REGION OF UPPER SYNOPTIC SYSTEM SHOULD SUPPORT CONTINUED DEVELOPMENT NEWD INTO WRN IA/NWRN MO THROUGH THE EVENING. DESPITE LARGELY MERIDIONAL MID AND HIGH-LEVEL WIND FIELDS...BACKED SURFACE WINDS E/SE OF THE SURFACE LOW ARE RESULTING IN VERTICAL SHEAR PROFILES SUPPORTIVE OF SUPERCELLS WITH AN ANTICIPATED CONTINUING THREAT OF LARGE HAIL...LOCALLY DAMAGING WIND GUSTS AND PERHAPS A FEW TORNADOES. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP... 42119626 42249580 42129513 41199411 39519384 39119413 38949469 39219512 WWWW From Mcd at goshenarc.org Fri Apr 7 00:55:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:55:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070054 SWOMCD SPC MCD 070053 ARZ000-MOZ000-OKZ000-TXZ000-070230- MESOSCALE DISCUSSION 0448 NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK CONCERNING...TORNADO WATCH 155...157... VALID 070053Z - 070230Z ...HIGH POTENTIAL FOR TORNADOES AND LARGE HAIL WITH DISCRETE SUPERCELLS NOW MOVING ACROSS ERN OK.... LATEST RADAR IMAGERY SHOWS SEVERAL SUPERCELL TSTMS EXTENDING FROM FAR SE KS TO SE OK. ENVIRONMENTAL PARAMETERS ARE VERY FAVORABLE FOR STORM ROTATION...WITH 0-1 SRH NEAR 400 M2/S2. HASKELL OK PROFILER AND VAD DATA FROM BOTH TULSA AND FORT SMITH SHOW VERY IMPRESSIVE DIRECTION/SPEED SHEAR WITH 50 KT OBSERVED NEAR 1 KM. LAMONT AND PURCELL PROFILER DATA ALSO SHOW 100KT DOWN TO 3KM...INDICATING THE EXTREMELY STRONG WINDS...ASSOCIATED WITH EJECTING JET STREAK. SEVERAL OF THESE STORMS HAVE ALREADY PRODUCED BRIEF TORNADOES...INCLUDING A RECENT REPORT OF A TORNADO WEST OF EUFAULA DAM IN HASKELL CO JUST BEFORE 730PM. STORM SIGNATURES DO INDICATE THAT STORMS ARE FEELING THE EFFECTS OF THE EXTREME SHEAR. HOWEVER...THE STORMS /BY MAINTAINING SOME SPACE BETWEEN CELLS/ ARE NOT DESTRUCTIVELY INTERFERING...WHICH DOES INCREASE THE POTENTIAL FOR TORNADOES. BEST POTENTIAL APPEARS TO BE ACROSS SE OK INTO WCNTRL AR. AIRMASS IS SLIGHTLY MORE STABLE ACROSS NW AR...BUT MOISTURE IS RAPIDLY RETURNING IN A SLIGHTLY ELEVATED FASHION. STRENGTH OF SHEAR SUGGESTS SEVERE THREAT WILL SPREAD INTO PORTIONS OF WW 157 /INTO NRN AND WRN AR/ THROUGH LATER THIS EVENING. ..TAYLOR.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...FWD...OUN... 33789476 33839619 35609549 36979517 36929403 35429388 34569387 WWWW From Mcd at goshenarc.org Fri Apr 7 01:30:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 21:30:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070129 SWOMCD SPC MCD 070129 KSZ000-MOZ000-IAZ000-NEZ000-SDZ000-070300- MESOSCALE DISCUSSION 0449 NWS STORM PREDICTION CENTER NORMAN OK 0829 PM CDT THU APR 06 2006 AREAS AFFECTED...N-CNTRL AND ERN NEB / ERN KS CONCERNING...SEVERE THUNDERSTORM WATCH 154...158... VALID 070129Z - 070300Z SEVERE WEATHER THREAT IS EXPECTED TO SHIFT E OF WW 154 BY 02Z...THEREFORE THIS WW WILL BE ALLOWED TO EXPIRE AT THAT TIME. ELSEWHERE...OVERALL SEVERE WEATHER POTENTIAL APPEARS TO BE DIMINISHING ACROSS N-CNTRL AND NERN NEB...SUGGESTING WW 158 COULD POSSIBLY BE CANCELLED EARLY. AS OF 0120Z...REGIONAL RADAR IMAGERY SHOWED A LINE OF STRONG TO POTENTIALLY SEVERE TSTMS FROM BURT COUNTY NEB SWD ALONG THE MO RIVER INTO BROWN AND JACKSON COUNTIES IN NERN KS. DESPITE LARGELY MERIDIONAL INDIVIDUAL CELL MOTIONS...OVERALL LINE MOVEMENT IS MORE EWD WHICH SHOULD TAKE THIS DEVELOPMENT INTO WW 160 BY 02Z. FARTHER TO THE N...WIDESPREAD CONVECTION HAS RESULTED IN CONSIDERABLE STABILIZATION OF AIR MASS WITH MOST VIGOROUS DEVELOPMENT OCCURRING ALONG NRN FRINGE OF PRECIPITATION SHIELD FROM GREGORY AND CHARLES MIX COUNTIES EWD TO YANKTON COUNTY IN SD. THESE STRONGER STORMS WILL REMAIN CAPABLE OF PRIMARILY MARGINALLY SEVERE HAIL. LITTLE ADDITIONAL DESTABILIZATION IS ANTICIPATED TONIGHT OWING TO THE LOSS OF DAYTIME HEATING AND AFOREMENTIONED WIDESPREAD COLD POOL DEVELOPMENT. THEREFORE...SHOULD CURRENT CONVECTIVE TRENDS CONTINUE...PORTIONS OF WW 158 COULD BE CANCELLED EARLY /SPECIFICALLY FROM SW TO NE/. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...FSD...OAX...TOP...ICT...GID...LBF...UNR... 37049626 43110057 43019659 40039540 37049503 WWWW From Mcd at goshenarc.org Fri Apr 7 02:28:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 22:28:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070227 SWOMCD SPC MCD 070227 TXZ000-OKZ000-070330- MESOSCALE DISCUSSION 0450 NWS STORM PREDICTION CENTER NORMAN OK 0927 PM CDT THU APR 06 2006 AREAS AFFECTED...NERN INTO CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 156... VALID 070227Z - 070330Z SOME THREAT OF MARGINALLY SEVERE HAIL MAY PERSIST FOR THE NEXT COUPLE OF HOURS ACROSS PARTS OF CNTRL TX. AN ADDITIONAL WW IS NOT ANTICIPATED. AS OF 02Z...MESOANALYSIS INDICATED PACIFIC COLD FRONT FROM E OF ADM SWD THROUGH THE METROPLEX TO W OF TPL. STRONG TO SEVERE TSTMS WHICH HAVE PERSISTED FOR THE PAST COUPLE OF HOURS FROM NEAR ACT TO AUS HAVE WEAKENED CONSIDERABLY OVER THE PAST HALF HOUR...PRESUMABLY OWING TO STRENGTHENING CAP ACROSS MODERATELY UNSTABLE...PRE-FRONTAL AIRMASS. CURRENT WATER VAPOR IMAGERY SUGGESTS THAT THE SRN FRINGE OF LARGE-SCALE FORCING ASSOCIATED WITH CNTRL PLAINS UPPER LOW IS RAPIDLY SHIFTING NE OF THE REGION. THUS...DESPITE THE PRESENCE OF THE MODERATE INSTABILITY AND STRONG SHEAR PROFILES...IT APPEARS THAT A MORE ORGANIZED SEVERE THREAT WILL CONTINUE TO DIMINISH. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...HGX...FWD...OUN...EWX... 34049586 33969479 33409445 30869560 30239713 30259778 30949808 33999639 WWWW From Mcd at goshenarc.org Fri Apr 7 02:52:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 22:52:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070251 SWOMCD SPC MCD 070251 MOZ000-IAZ000-MNZ000-KSZ000-NEZ000-SDZ000-070445- MESOSCALE DISCUSSION 0451 NWS STORM PREDICTION CENTER NORMAN OK 0951 PM CDT THU APR 06 2006 AREAS AFFECTED...NRN MO/WRN IA...SWRN MN AND SERN SD CONCERNING...TORNADO WATCH 160... VALID 070251Z - 070445Z THREAT FOR TORNADOES APPEARS TO HAVE DIMINISHED AS BOUNDARY LAYER CONTINUES TO DECOUPLE. HOWEVER...THREAT FOR SVR HAIL WILL STILL EXIST FOR SEVERAL MORE HRS OVER MUCH OF WW 160. REDEVELOPMENT OF ISOLATED SVR STORMS WILL REMAIN POSSIBLE ALONG WRN PORTIONS OF WW 160 /WRN IA/ OVER THE NEXT FEW HRS...AS MAIN MID LEVEL FORCING INTERACTS WITH REMAINING MODERATE INSTABILITY /MUCAPES AROUND 1500 J/KG/. MAIN THREAT WITH THIS ACTIVITY WILL BE SVR HAIL...ALTHOUGH AN ISOLATED TORNADO WILL BE POSSIBLE THROUGH AROUND MIDNIGHT OVER SWRN IA WHERE AIRMASS HAS NOT BEEN CONVECTIVELY STABILIZED YET. FARTHER NORTH...MORE MARGINAL INSTABILITY /MUCAPES LESS THAN 1000 J/KG/ ACROSS FAR NWRN IA/SERN SD AND SWRN MN/ WILL SUPPORT MORE LIMITED SVR HAIL POTENTIAL. THUS A NEW WW IS NOT ANTICIPATED NORTH OF WW 160. FARTHER SOUTH AN ORGANIZED CONVECTIVE LINE OVER CENTRAL MO...ON THE NOSE OF THE MID LEVEL JET...WILL CONTINUE TO PUSH THROUGH SERN PORTION OF WW 160 /CENTRAL MO/ AND INTO NERN MO OVER THE NEXT FEW HRS. GIVEN WANING INSTABILITY AND DEEPENING STABLE LAYER IN THE LOWEST FEW THOUSAND FEET...A SVR WIND THREAT IS NOT ANTICIPATED TO BE ORGANIZED ENOUGH TO WARRANT A NEW WW OVER NERN MO /EAST OF WW 160/. ..CROSBIE.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...MPX...DMX...EAX...FSD...OAX...TOP... 44149680 43939777 43319714 42299637 41309594 39759527 39109505 38919373 39009273 39979196 41719231 43609452 WWWW From Mcd at goshenarc.org Fri Apr 7 03:23:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 23:23:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070322 SWOMCD SPC MCD 070321 ARZ000-MOZ000-OKZ000-KSZ000-070445- MESOSCALE DISCUSSION 0452 NWS STORM PREDICTION CENTER NORMAN OK 1021 PM CDT THU APR 06 2006 AREAS AFFECTED...SWRN MO / NW AND N-CNTRL AR CONCERNING...TORNADO WATCH 157...159... VALID 070321Z - 070445Z THROUGH 0430Z...THE GREATEST SEVERE WEATHER THREAT WILL EXIST FROM HRO TO W OF RUE EWD TO E OF UNO SWD TO LIT. ISOLATED TORNADOES...LOCALLY DAMAGING WINDS AND LARGE HAIL REMAIN POSSIBLE WITH THE MOST INTENSE STORMS. AS OF 03Z...REGIONAL RADAR IMAGERY INDICATED A BROKEN LINE OF STRONG TO SEVERE STORMS FROM BOONE COUNTY AR SWWD TO SCOTT COUNTY AR MOVING 245/40-50 KTS. EMBEDDED CELLS OVER BOONE AND LOGAN/YELL COUNTIES INDICATE THE PRESENCE OF MESOCYCLONES WITH REFLECTIVITY DATA SUGGESTING HP SUPERCELL CHARACTERISTICS. LOCAL PROFILERS AND VWPS INDICATE THAT INFLOW AIR MASS ACROSS THE NWRN QUARTER OF AR IS STRONGLY SHEARED WITH 0-1 KM SRH OF 400-500 M2/S2 AND DEEP LAYER SHEAR OF 65-75 KTS. PRIMARY UNCERTAINTY IS WHETHER THESE STORMS ARE TRULY SURFACE-BASED OR SLIGHTLY ELEVATED ABOVE A NEAR SURFACE INVERSION. RELATIVELY LIGHT SURFACE WINDS...GROUND CLUSTER SIGNATURE OBSERVED ON LIT 88D AND RUC FORECAST SOUNDINGS DO SUGGEST THAT THIS ACTIVITY MAY BE ELEVATED TO SOME DEGREE WHICH MAY TEND TO LIMIT A GREATER TORNADO THREAT. HOWEVER...GIVEN THE STRONG SHEAR AND UNCERTAINTY REGARDING THE DEPTH OF THIS INVERSION...POTENTIAL FOR ISOLATED TORNADOES STILL EXISTS...IN ADDITION TO LARGE HAIL AND LOCALLY DAMAGING WINDS. FARTHER TO THE N IN MO...COMPARATIVELY WEAKER INSTABILITY APPEARS TO BE LIMITING STORM INTENSITY. SHOULD CURRENT TRENDS CONTINUE...AN ADDITIONAL WW MAY NOT BE NEEDED ACROSS E-CNTRL AND PARTS OF SERN MO. HOWEVER...A NEW TORNADO WATCH MAY BECOME NECESSARY WITHIN THE NEXT COUPLE OF HOURS OVER NERN AR PERHAPS INTO FAR SERN MO. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...LZK...SGF...EAX...TSA... 38849490 38819167 34639137 34719462 WWWW From Mcd at goshenarc.org Fri Apr 7 14:09:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 10:09:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071408 SWOMCD SPC MCD 071407 KYZ000-TNZ000-INZ000-ALZ000-ILZ000-MSZ000-MOZ000-ARZ000-071600- MESOSCALE DISCUSSION 0453 NWS STORM PREDICTION CENTER NORMAN OK 0907 AM CDT FRI APR 07 2006 AREAS AFFECTED...PARTS OF ERN AR...WRN TN AND MIDDLE TN...NRN MS...SERN MO...WRN KY AND SRN IL...SWRN IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071407Z - 071600Z PARTS OF LOWER AND MIDDLE MS VALLEY AND TN VALLEY ARE BEING MONITORED FOR SURFACE BASED THUNDERSTORM DEVELOPMENT. THREAT FOR SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND A FEW STRONG TORNADOES IS EXPECTED TO INCREASE LATER THIS MORNING AND INTO THE AFTERNOON. A TORNADO WATCH WILL LIKELY BE NEEDED FOR PARTS OF THIS AREA WITHIN THE NEXT 1 TO 2 HOURS. EARLY THIS MORNING A LONE ELEVATED STORM CONTINUES ACROSS WRN TN. THIS STORM IS DEVELOPING WITHIN A ZONE OF ASCENT AND LOW LEVEL WARM ADVECTION ALONG A SWLY LOW LEVEL JET. VISIBLE IMAGERY SHOWS OTHER CLOUDS ON THE NRN EDGE OF THE THICKER STRATUS BEGINNING TO TAKE ON A MORE CONVECTIVE CHARACTER. LOW LEVEL MOISTURE WITH DEWPOINTS IN THE LOW TO MID 60S HAS SPREAD THROUGH THE LOWER MS VALLEY AND WRN PARTS OF THE TN VALLEY. MORNING RAOB DATA SHOW STEEPER MID LEVEL LAPSE RATES UPSTREAM THAT WILL LIKELY ADVECT EWD DURING THE DAY. THIS WILL CONTRIBUTE TO DESTABILIZATION AS LOW CLOUDS CONTINUE TO MIX OUT. MORNING ACARS AND RAOB DATA ALSO INDICATE A WEAK CAP REMAINING AND SUGGEST ONLY MODEST BOUNDARY LAYER WARMING IS NEEDED FOR STORMS TO BECOME SURFACE BASED. WV IMAGERY SHOWS A PRONOUNCED DRYSLOT MOVING INTO PORTIONS OF THE LOWER MS VALLEY BUT WITH AN AXIS OF DEEPER MOISTURE FROM MS NWD THROUGH ERN AR...WRN TN...SERN MO AND WRN KY. ADDITIONAL STORMS WILL LIKELY DEVELOP LATER THIS MORNING AND INTO THE AFTERNOON WITHIN THIS AXIS OF DEEPER MOISTURE AS THE CAP WEAKENS AND AS A VORT MAX PIVOTS SEWD TOWARD THE LOWER MS VALLEY. THE NATURE OF THE LOW LEVEL AND DEEP LAYER VERTICAL SHEAR PROFILES WILL SUPPORT SUPERCELL STRUCTURES WITH LARGE HAIL AND A FEW STRONG TORNADOES POSSIBLE. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...HUN...PAH...MEG...LZK... 36838661 35278727 34128880 34349176 37778961 38158759 WWWW From Mcd at goshenarc.org Fri Apr 7 15:48:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 11:48:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071547 SWOMCD SPC MCD 071547 ALZ000-MSZ000-ARZ000-LAZ000-071745- MESOSCALE DISCUSSION 0454 NWS STORM PREDICTION CENTER NORMAN OK 1047 AM CDT FRI APR 07 2006 AREAS AFFECTED...ERN AR...NERN LA...CNTRL AND NRN MS...CNTRL AND NRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071547Z - 071745Z THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER PORTIONS OF THE LOWER MS VALLEY AND SPREAD EWD DURING THE DAY. SUPERCELLS WITH VERY LARGE HAIL AND A FEW STRONG TORNADOES WILL BE THE PRIMARY THREATS. A WW WILL LIKELY BE NEEDED FOR MUCH OF THIS AREA WITHIN THE HOUR. THIS MORNING AN AXIS OF RICHER LOW LEVEL MOISTURE WITH DEWPOINTS IN THE LOW TO MID 60S HAS SPREAD NEWD THROUGH THE LOWER MS VALLEY. THE LATEST VISIBLE IMAGERY CONTINUES TO SHOW EXTENSIVE STRATUS. HOWEVER...MIXING IS INCREASING AROUND THE EDGES OF THIS STRATUS DECK WITH CLOUDS BECOMING MORE CONVECTIVE IN NATURE ACROSS ERN AR. THE SPECIAL 14Z RAOB FROM JACKSON MS SHOWED SOME COOLING HAS OCCURRED IN THE 850-700 MB LAYER WITH LITTLE CAP REMAINING. THIS SUGGEST ONLY A MODEST AMOUNT OF SURFACE HEATING IS NEEDED WITHIN THE MOIST AXIS TO PROMOTE SURFACE BASED THUNDERSTORM INITIATION. THE ATMOSPHERE WILL CONTINUE TO DESTABILIZE AS STEEP MID LEVEL LAPSE RATES ADVECT EWD ABOVE THE WARMING BOUNDARY LAYER. STORMS ARE EXPECTED TO DEVELOP INITIALLY OVER SERN AR AND NRN MS THEN SPREAD EWD. A 30-40 KT SWLY LOW LEVEL JET WILL PERSIST DOWNSTREAM FROM SEWD ADVANCING UPPER TROUGH. THIS FEATURE AND A STRONG WSWLY MID LEVEL JET WILL CONTRIBUTE TO FAVORABLE LOW LEVEL AND DEEP LAYER SHEAR FOR SUPERCELLS. GIVEN THE NATURE OF THE THERMODYNAMIC AND KINEMATIC PROFILES AND EXPECTED DISCRETE MODES...A FEW STRONG TORNADOES WILL BE POSSIBLE. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN...MEG...JAN...LZK...SHV... 33269277 34719142 34958843 34788574 33298596 32039145 WWWW From Mcd at goshenarc.org Fri Apr 7 17:25:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 13:25:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071724 SWOMCD SPC MCD 071723 OHZ000-INZ000-ILZ000-071930- MESOSCALE DISCUSSION 0455 NWS STORM PREDICTION CENTER NORMAN OK 1223 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL IL...CNTRL IND...THROUGH W CNTRL OH CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071723Z - 071930Z PORTIONS OF THE OH VALLEY ARE BEING MONITORED FOR THUNDERSTORM INITIATION. ONCE STORMS DEVELOP...SUPERCELLS AND LINES APPEAR LIKELY WITH LARGE HAIL AND DAMAGING WIND THE PRIMARY THREATS. AREA IS BEING MONITORED FOR A POSSIBLE WW. EARLY THIS AFTERNOON LOW LEVEL MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO LOWER 60S CONTINUE TO ADVECT NEWD TOWARD THE OH VALLEY. HOWEVER...WITH THE LOW LEVEL FLOW EXPECTED TO REMAIN MORE WLY...THE RICHER MOISTURE IS EXPECTED TO REMAIN S OF THIS AREA. THE MOIST BOUNDARY LAYER SOMEWHAT SHALLOW...AND TREND HAS BEEN FOR THE SURFACE DEWPOINTS TO MIX DOWN. NEVERTHELESS...SURFACE HEATING AND STEEP MID LEVEL LAPSE RATES WILL CONTRIBUTE TO MLCAPE FROM 1000 TO 1500 J/KG. AN INCREASE IN CUMULUS CONTINUES TO BE OBSERVED WITHIN THE WARM SECTOR S OF A SWD MOVING COLD FRONT THAT CURRENTLY EXTENDS FROM NRN OH WWD THROUGH NRN IND AND NRN IL. POTENTIAL FOR STORMS TO DEVELOP ALONG AND AHEAD OF THE FRONT WILL INCREASE THROUGH THIS AFTERNOON AS THE BOUNDARY LAYER CONTINUES TO WARM. LARGELY WLY UNIDIRECTIONAL BUT STRONG SHEAR PROFILES WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS...BUT SOME STORMS MAY ALSO EVOLVE INTO LINES OR CLUSTERS. WITH THE PRIMARY LOW LEVEL JET EXPECTED TO REMAIN S OF THIS REGION...LOW LEVEL SHEAR SHOULD REMAIN MODEST. THIS IN CONJUNCTION WITH THE DRYER BOUNDARY LAYER SUGGEST THE PRIMARY THREATS SHOULD REMAIN LIMITED TO LARGE HAIL AND DAMAGING WIND. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX...LSX... 39358373 38678827 38828993 39798993 40518892 40818728 41178564 40478343 WWWW From Mcd at goshenarc.org Fri Apr 7 18:36:54 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 14:36:54 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071835 SWOMCD SPC MCD 071835 WVZ000-OHZ000-VAZ000-NCZ000-TNZ000-KYZ000-INZ000-071930- MESOSCALE DISCUSSION 0456 NWS STORM PREDICTION CENTER NORMAN OK 0135 PM CDT FRI APR 07 2006 AREAS AFFECTED...MUCH OF OH/ERN KY/WV/FAR SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071835Z - 071930Z WW WILL BE ISSUED SOON FOR MUCH OF CENTRAL/SRN OH SWD ACROSS ERN KY/WRN WV AND FAR SWRN VA. AIR MASS ACROSS THE DISCUSSION AREA WILL CONTINUE TO DESTABILIZE /MLCAPE AROUND 1000 J/KG NOW INTO FAR SWRN OH/ERN KY/TN/ AS LOW-LEVEL MOISTURE RETURNS ENEWD THROUGH THE MID-UPPER OH/TN VALLEYS. THIS COMBINED WITH STRONG SURFACE HEATING AND STEEPENING MID LEVEL LAPSE RATES PER REGIONAL 18Z SOUNDINGS WILL RESULT IN MODERATE INSTABILITY ACROSS THE REST OF THIS AREA. SWLY MID-LEVEL WINDS WILL CONTINUE TO STRENGTHEN THIS AFTERNOON AS 60-80 JET TRANSLATES ENE ACROSS THE OH VALLEY. DEEP LAYER SHEAR ALREADY OVER 50 KT WILL SUPPORT ORGANIZED STRONG TO SEVERE STORMS. ALTHOUGH WIND FIELDS ARE GENERALLY UNI-DIRECTIONAL WITH LITTLE LOW-LEVEL DIRECTIONAL SHEAR...STRONG LOW-LEVEL SPEED SHEAR AS INDICATED BY THE 18Z PIT SOUNDING SUGGESTS THE POTENTIAL FOR TORNADOES. A FEW SHOWERS/ISOLATED THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS ERN KY INTO WV...WITH UPSTREAM ACTIVITY ACROSS IND AND CENTRAL KY EXPECTED TO MOVE INTO OH/ERN KY BY 20Z. ..PETERS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...PBZ...RLX...CLE...MRX...JKL...ILN...LMK...IWX...OHX... 40938473 41228324 41048060 38738051 36528169 36288400 36408477 37418494 WWWW From Mcd at goshenarc.org Fri Apr 7 19:25:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 15:25:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071923 SWOMCD SPC MCD 071922 KYZ000-ALZ000-TNZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-LAZ000-072115- MESOSCALE DISCUSSION 0457 NWS STORM PREDICTION CENTER NORMAN OK 0222 PM CDT FRI APR 07 2006 AREAS AFFECTED...NERN LA...ERN AR...WRN AND MIDDLE TN...CNTRL AND NRN MS AND AL...SERN MO...SRN IL...SRN IND AND WRN THROUGH CNTRL KY CONCERNING...TORNADO WATCH 162...163... VALID 071922Z - 072115Z THREAT FOR A FEW STRONG LONG TRACK TORNADOES IS EXPECTED TO PERSIST WITH STORMS MOVING THROUGH WRN AND MIDDLE TN INTO WRN AND CNTRL KY NEXT FEW HOURS. ISOLATED TORNADOES REMAIN POSSIBLE FROM SRN IL INTO SRN IND. OTHER STORMS ARE EXPECTED TO DEVELOP FARTHER S ACROSS PARTS OF SERN AR...NRN LA INTO MS AND AL THIS AFTERNOON AND EVENING. THESE STORMS WILL POSE A THREAT FOR A FEW STRONG TORNADOES AND VERY LARGE HAIL ONCE THEY DEVELOP. THE ATMOSPHERE REMAINS MODERATELY UNSTABLE OVER THE LOWER MS VALLEY AND PARTS OF THE SERN U.S. WITH MLCAPE FROM 1500 TO 2000 J/KG FROM NERN LA...SERN AR INTO CNTRL AND NRN MS AND NRN AL. THE 18Z RAOB FROM JACKSON STILL SHOWED SOME CONVECTIVE INHIBITION IN THE 850 MB-700 MB LAYER. WARMING AND MIXING WITHIN THE BOUNDARY LAYER AND HEIGHT FALLS ASSOCIATED WITH SEWD ADVANCING UPSTREAM VORT MAX SUGGEST THE POTENTIAL FOR INITIATION WILL BECOME INCREASINGLY LIKELY WITHIN ZONE OF MODEST WARM ADVECTION OVER THE LOWER MS VALLEY. THE STRONG MID LEVEL JET ASSOCIATED WITH THE UPSTREAM SHORTWAVE TROUGH WILL SHIFT SLOWLY SEWD AND REMAIN IN A FAVORABLE POSITION RELATIVE TO THE LOW LEVEL JET FOR VERTICAL SHEAR CONDUCIVE FOR SUPERCELLS WITH STRONG LOW LEVEL MESOCYCLONES. NEW STORMS THAT DEVELOP WILL LIKELY REMAIN DISCRETE FOR SEVERAL HOURS. KINEMATIC AND THERMODYNAMIC PROFILES WILL CONTINUE TO SUPPORT A THREAT FOR VERY LARGE HAIL AND STRONG TORNADOES. TORNADOES CONTINUE TO BE CONFIRMED WITH SUPERCELLS MOVING THROUGH WRN AND MIDDLE TN AS WELL AS PORTIONS OF WRN AND CNTRL KY. THIS ACTIVITY WILL LIKELY PERSIST AND SHIFT ENEWD NEXT SEVERAL HOURS. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...BMX...HUN...PAH...MEG...JAN...LSX...LZK...SHV... 32878673 31849259 35109139 38058958 37828555 WWWW From Mcd at goshenarc.org Fri Apr 7 20:59:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 16:59:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072056 SWOMCD SPC MCD 072056 INZ000-KYZ000-ILZ000-MOZ000-072230- MESOSCALE DISCUSSION 0458 NWS STORM PREDICTION CENTER NORMAN OK 0356 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL IL...CNTRL IND CONCERNING...TORNADO WATCH 164... VALID 072056Z - 072230Z GREATEST TORNADIC THREAT SHOULD BE CONFINED TO THE FAR SRN PORTION OF WW164. ADDITIONAL TSTMS SHOULD CONTINUE TO DEVELOP ALONG SWD MOVING COLD FRONT ACROSS NRN PORTION OF WW164. LARGE HAIL WILL BE THE MAIN THREAT WITH ALL STORMS. SEVERAL CLUSTERS OF MULTICELLS AND SUPERCELLS TSTMS HAVE DEVELOPED IN A MODERATELY UNSTABLE AIRMASS WITH MLCAPES OF 1000 TO 2000 J/KG AND STRONG MID/UPPER-LEVEL SPEED SHEAR. STEEP MID-LAPSE LEVEL RATES AS EVIDENCED BY REGIONAL 18Z RAOBS WILL CONTINUE TO SUPPORT LARGE HAIL...SOME OF WHICH WILL BE SIGNIFICANT GIVEN THE DEGREE OF MID-LEVEL COOLING THAT HAS OCCURRED. LOW-LEVEL WIND FIELDS ARE SUPPORTIVE OF TORNADIC STORMS ALONG THE SRN PERIPHERY OF WW164 AND FURTHER S WHERE NEAR-SURFACE BACKING EXISTS. FURTHER N...THE IND VAD PROFILER SHOWS A UNIDIRECTIONAL WSW LOW-LEVEL SIGNATURE WITH ONLY MODEST SPEED SHEAR. ADDITIONAL CONVECTIVE DEVELOPMENT WILL LIKELY CONTINUE ALONG THE SWD-MOVING COLD FRONT IN VICINITY OF DEC TO MIE AT 20Z. THE STEEP LAPSE RATES ALOFT WILL SUPPORT LARGE HAIL...HOWEVER WEAK AND UNIDIRECTIONAL LOW-LEVEL WIND FIELDS AS EVIDENCED BY ILX AND LSX VAD PROFILERS SUPPORT A DIMINISHING TORNADIC THREAT ACROSS CNTRL IL. ..GRAMS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IND...PAH...ILX...LSX... 40128970 40298819 40368555 40178493 39328494 38928505 38728543 38798670 38608821 38578965 38799022 39578988  From Mcd at goshenarc.org Fri Apr 7 21:01:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 17:01:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072057 SWOMCD SPC MCD 072057 VAZ000-WVZ000-MDZ000-PAZ000-OHZ000-NCZ000-TNZ000-KYZ000-SCZ000-GAZ000-INZ000-072230- MESOSCALE DISCUSSION 0459 NWS STORM PREDICTION CENTER NORMAN OK 0357 PM CDT FRI APR 07 2006 AREAS AFFECTED...CENTRAL AND SRN OH/ERN KY/ERN TN/WRN WV/FAR WRN VA/FAR WRN NC CONCERNING...TORNADO WATCH 165... VALID 072057Z - 072230Z PARAMETERS REMAIN FAVORABLE FOR SUPERCELLS PRODUCING TORNADOES... LARGE HAIL AND DAMAGING WINDS...ESPECIALLY ACROSS THE WRN/SRN PARTS OF WW 165. NUMEROUS THUNDERSTORMS CONTINUE TO DEVELOP/SPREAD ENEWD INTO WRN OH AND ERN KY WHERE THE AIR MASS REMAINED MODERATELY UNSTABLE. MODERATE INSTABILITY EXTENDED SWD INTO ERN TN WITH STRONG/SEVERE STORMS OVER MIDDLE TN EXPECTED TO MOVE INTO SRN PART OF WW 165 DURING THE NEXT FEW HOURS. AREA WSR-88D VADS INDICATED UNI- DIRECTIONAL WIND PROFILES WITH STRONG DEEP LAYER SHEAR SUPPORTING A CONTINUED POTENTIAL FOR SPLITTING SUPERCELLS. STRONGEST LOW-LEVEL SHEAR WAS LOCATED ACROSS THE SRN PART OF WW 165 WHERE THE TORNADO THREAT WILL BE THE GREATEST. FARTHER NE ACROSS CENTRAL/ERN OH...STRONG SURFACE HEATING HAS RESULTED IN DOWNWARD MIXING OF DRY AIR AND AT LEAST 30 DEGREE SURFACE DEWPOINT DEPRESSIONS. STORMS MOVING INTO THIS ENVIRONMENT MAY HAVE A GREATER POTENTIAL FOR DAMAGING WINDS. FARTHER EAST ACROSS CENTRAL/ERN WV INTO NRN VA/WRN MD...30-50 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW ORGANIZED STORMS. AIR MASS HAS BEEN SLOW TO DESTABILIZE WITH WEAK INSTABILITY EXPECTED TO LIMIT SEVERE THREAT EAST OF WW 165...AT LEAST FOR THE NEXT 1-2 HOURS. ..PETERS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...PBZ...RLX...CLE...GSP...MRX...JKL...FFC...ILN...LMK...IWX...OHX...IND... 35128555 36788510 40648484 40648157 39808066 39417788 38577818 36878108 36428171 34948315  From Mcd at goshenarc.org Fri Apr 7 21:55:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 17:55:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072153 SWOMCD SPC MCD 072153 LAZ000-ARZ000-TXZ000-072300- MESOSCALE DISCUSSION 0460 NWS STORM PREDICTION CENTER NORMAN OK 0453 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN LA INTO PORTIONS OF ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 072153Z - 072300Z POTENTIAL FOR ISOLATED SEVERE STORMS WILL EXIST THROUGH THE EVENING. CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE WW ISSUANCE. VISIBLE AND WATER VAPOR SATELLITE DATA SUGGEST THAT A SEWD MOVING GRAVITY WAVE COUPLED WITH INCREASED LARGE-SCALE FORCING AHEAD OF VORTICITY MAXIMUM PIVOTING SEWD ACROSS NWRN TX HAVE CONTRIBUTED TO BACKBUILDING TSTM DEVELOPMENT THIS AFTERNOON INTO S-CNTRL AR AND N-CNTRL AR. ADDITIONAL SWWD DEVELOPMENT WILL BE POSSIBLE THIS EVENING AS THE FORCING FOR ASCENT CONTINUES TO INCREASE AHEAD OF AFOREMENTIONED VORTICITY MAXIMUM. AMBIENT PRE-FRONTAL AIR MASS REMAINS MODERATELY UNSTABLE LATE THIS AFTERNOON WITH MLCAPES OF 1000-2000 J/KG...AND WHEN COUPLED WITH STRONG UNIDIRECTIONAL WIND PROFILES...POTENTIAL EXISTS FOR SPLITTING SUPERCELLS CAPABLE OF LARGE HAIL...LOCALLY DAMAGING WINDS AND PERHAPS A COUPLE OF TORNADOES. CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED...AND SHOULD IT BECOME MORE APPARENT SIGNIFICANT TSTM DEVELOPMENT WILL BECOME ESTABLISHED W OF WW 163 AN ADDITIONAL WW MAY BE REQUIRED. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...SHV...HGX...FWD... 33469340 33289303 32149291 31509284 30759375 30309476 30629552 31379583 32259527 WWWW From Mcd at goshenarc.org Fri Apr 7 22:14:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 18:14:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072212 SWOMCD SPC MCD 072212 ALZ000-TNZ000-MSZ000-ARZ000-LAZ000-072345- MESOSCALE DISCUSSION 0461 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT FRI APR 07 2006 AREAS AFFECTED...SERN AR / NERN LA / NRN AND CNTRL MS / NRN AND CNTRL AL CONCERNING...TORNADO WATCH 163... VALID 072212Z - 072345Z THROUGH 00Z...THE GREATEST POTENTIAL FOR TORNADOES /SOME OF THEM SIGNIFICANT/ IS EXPECTED IN A SW-NE CORRIDOR FROM SE OF GLH TO NEAR TUP TO NE MSL. SW-NE ORIENTED BAND OF TSTMS CONTINUE TO BECOME BETTER ORGANIZED EARLY THIS EVENING FROM THE ARKLAMS NEWD ACROSS NRN MS WITH SEVERAL STORM SPLITS...SUGGESTING UNIDIRECTIONAL VERTICAL SHEAR PROFILES. THIS NOTION IS CONFIRMED BY CURRENT OKOLONA MS PROFILER DATA WHICH EXHIBIT RELATIVELY STRONG VERTICAL SPEED SHEAR WITH AROUND 60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 100-150 M2/S2. 21Z JAN SOUNDING SHOWED THE PRESENCE OF STEEP MID-LEVEL LAPSE RATES ATOP A LOW-LEVEL MEAN MIXING RATIO OF 10-11 G/KG...WHICH WERE CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. THIS SOUNDING ALSO EXHIBITED A MODERATELY HIGH LCL /1800 M/ OWING TO BOUNDARY-LAYER TEMPERATURE-DEWPOINTS SPREADS OF AROUND 25 F. DESPITE THE MODEST LOW-LEVEL SHEAR AND LCL HEIGHTS...POTENTIAL WILL EXIST FOR TORNADOES WITH ALL RIGHT MOVING SUPERCELLS ACROSS WW 163 AREA. COOLING/MOISTENING OF BOUNDARY-LAYER COUPLED WITH INCREASING LOW-LEVEL SHEAR AFTER 00Z...SUGGEST THAT THE POTENTIAL FORT A FEW SIGNIFICANT TORNADOES MAY INCREASE AT THIS TIME. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MOB...MEG...JAN...LZK...LCH...SHV... 34599268 35768601 32518609 31269275 WWWW From Mcd at goshenarc.org Fri Apr 7 22:40:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 18:40:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072238 SWOMCD SPC MCD 072238 VAZ000-NCZ000-WVZ000-080015- MESOSCALE DISCUSSION 0462 NWS STORM PREDICTION CENTER NORMAN OK 0538 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 072238Z - 080015Z POTENTIAL FOR LOCALLY DAMAGING WINDS IS EXPECTED TO DEVELOP E OF WW 166 BY 23Z. SHOULD ONGOING STORMS MAINTAIN THEIR INTENSITY...A WW MAY BE REQUIRED. TRENDS IN REGIONAL RADAR DATA SUGGEST THAT A COLD POOL MAY BE ORGANIZING WITH ONGOING LINE OF TSTMS EXTENDING FROM NE OF SSU TO W OF BLF. DOWNSTREAM AIR MASS OVER CNTRL VA REMAINS QUITE WARM EARLY THIS EVENING WITH TEMPERATURES IN THE LOW TO MID 80S. ASSOCIATED STEEP LOW-LEVEL LAPSE RATES COUPLED WITH RELATIVELY DRY SUB-CLOUD CONDITIONS /I.E. TEMPERATURE-DEWPOINT SPREADS OF 30-40 DEGREES F/ SUGGEST THAT THIS COLD POOL MAY BE MAINTAINED E OF WW 166 WITH THE POTENTIAL FOR DAMAGING WINDS. PRIMARY UNCERTAINTY IS THE DURATION OF THIS THREAT OWING TO THE FACT THAT BOUNDARY-LAYER WILL BEGIN TO COOL OVER THE NEXT COUPLE OF HOURS WITH A RESULTANT WEAKENING OF LOW-LEVEL LAPSE RATES. CURRENT THINKING IS THAT THIS THREAT WILL REMAIN ISOLATED PRIOR TO AIR MASS STABILIZING. HOWEVER...IF IT APPEARS THAT A MORE ORGANIZED THREAT OF DAMAGING WINDS WILL DEVELOP E OF WW AREA...A WW MAY BE REQUIRED. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RAH...RNK... 38577933 38817877 38597776 37477788 36677825 36537882 36697958 WWWW From Mcd at goshenarc.org Sat Apr 8 02:22:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 22:22:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080221 SWOMCD SPC MCD 080221 VAZ000-NCZ000-WVZ000-080315- MESOSCALE DISCUSSION 0463 NWS STORM PREDICTION CENTER NORMAN OK 0921 PM CDT FRI APR 07 2006 AREAS AFFECTED...ERN KY CONCERNING...TORNADO WATCH 165... VALID 080221Z - 080315Z POTENTIAL FOR ISOLATED DAMAGING WINDS AND SEVERE HAIL MAY PERSIST BEYOND 03Z. HOWEVER...GIVEN THE ANTICIPATED LIMITED AREAL COVERAGE OF THIS THREAT...AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. AS OF 0205Z...REGIONAL RADAR IMAGERY SHOWED A PRE-FRONTAL CONVECTIVE LINE FROM LAWRENCE AND CABELL COUNTIES IN WRN WV SWWD TO WARREN AND SIMPSON COUNTIES IN S-CNTRL KY MOVING SEWD AT 30-40 KTS. RUC OBJECTIVE FIELDS SUGGEST THAT THE STRONGEST INSTABILITY EXISTS TO THE W FROM WRN TN SWD INTO MS AND AL WITH AIR MASS ONLY MARGINALLY UNSTABLE ACROSS ERN KY...TO THE N OF ONGOING STORMS OVER ERN TN. CURRENT JKL VWP INDICATES THAT AMBIENT ENVIRONMENT REMAINS STRONGLY SHEARED WITH 50 KT WSWLY WINDS AT .5 KM INCREASING TO 70 KTS AT 5 KM. THEREFORE...POTENTIAL WILL EXIST FOR LOCALLY DAMAGING WIND GUSTS AND MARGINALLY SEVERE HAIL WITH THE MOST INTENSE STORMS AS THEY MOVE THROUGH NARROW INSTABILITY AXIS. THIS THREAT AREA APPEARS TO BE QUITE LIMITED SPATIALLY AND AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RAH...RNK... 38577933 38817877 38597776 37477788 36677825 36537882 36697958 WWWW From Mcd at goshenarc.org Sat Apr 8 03:18:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 23:18:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080317 SWOMCD SPC MCD 080316 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-LAZ000-080445- MESOSCALE DISCUSSION 0464 NWS STORM PREDICTION CENTER NORMAN OK 1016 PM CDT FRI APR 07 2006 AREAS AFFECTED...NERN LA / NRN AND CNTRL MS / NRN AND CNTRL AL CONCERNING...TORNADO WATCH 169... VALID 080316Z - 080445Z POTENTIAL FOR ISOLATED TORNADOES IN ADDITION TO LARGE HAIL AND DAMAGING WINDS WILL CONTINUE ACROSS NRN AND CNTRL PARTS OF WW AREA THROUGH 04-05Z. IT APPEARS THAT THE GREATEST TORNADO THREAT WILL EXIST FROM JUST SW OF MSL EWD THROUGH HSV...EVENTUALLY INTO FAR NERN AL. FARTHER TO THE W...A CONVECTIVE LINE IS BECOMING PROGRESSIVELY MORE SW-NE ORIENTED OVER THE MS DELTA SWWD INTO N-CNTRL LA...SUGGESTING AN INCREASE IN DAMAGING WIND POTENTIAL FROM GLH TO GWO AND EVENTUALLY SWD TO I-20 OVER W-CNTRL MS. AS OF 03Z...REGIONAL RADAR IMAGERY SHOWED A SW-NE ORIENTED CONVECTIVE SHIELD FROM N-CNTRL LA ACROSS NRN MS...NWRN AL INTO MIDDLE AND ERN TN. SEVERAL SUPERCELLS ARE EMBEDDED WITHIN THIS LARGER COMPLEX...THE MOST INTENSE OF WHICH WAS LOCATED OVER LAWRENCE AND MORGAN COUNTIES IN N-CNTRL AL. KINEMATIC ENVIRONMENT /AS SAMPLED BY BHM VWP/ REMAINS STRONGLY SHEARED OWING TO 50-60 KT SWLY WINDS AT 1 KM WITH 0-1 KM SRH OF 350-400 M2/S2. 00Z BHM OBSERVED AND RUC FORECAST SOUNDINGS DO SUGGEST THAT INFLOW AIR MASS MAY BE SLIGHTLY CAPPED WITH MLCAPES OF 1000-1500 J/KG...THOUGH ONGOING INTENSE UPDRAFTS APPEAR TO BE SUCCESSFULLY OVERCOMING ANY CIN. EXTRAPOLATION OF CURRENT LAWRENCE/MORGAN COUNTY SUPERCELL TAKES IT VERY CLOSE TO HSV BY 330Z...AND TO NEAR THE AL/GA STATE LINE BY 430-05Z. FARTHER TO THE W...CONVECTION IS BECOMING MORE N-S ORIENTED FROM TALLAHATCHIE AND LEFLORE COUNTIES IN NWRN MS SWWD TO WEST CARROLL PARISH IN NERN MS. SHOULD THIS TREND CONTINUE...THIS CONVECTION WILL BECOME INCREASINGLY NORMAL TO 50-70 KT MID-LEVEL WIND FIELDS...SUGGESTING THE POTENTIAL FOR BOW OR LEWP ECHO EVOLUTION AND A RESULTANT INCREASING THREAT OF DAMAGING WINDS. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MOB...MEG...JAN...LIX...LZK...LCH...SHV... 33469206 35608530 32858543 30759199 WWWW From Mcd at goshenarc.org Sat Apr 8 03:56:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 23:56:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080355 SWOMCD SPC MCD 080355 LAZ000-ARZ000-TXZ000-080530- MESOSCALE DISCUSSION 0465 NWS STORM PREDICTION CENTER NORMAN OK 1055 PM CDT FRI APR 07 2006 AREAS AFFECTED...FAR ERN TX INTO WRN AND CNTRL LA CONCERNING...TORNADO WATCH 167... VALID 080355Z - 080530Z THROUGH 06Z...POTENTIAL FOR MAINLY DAMAGING WINDS WILL EXIST ACROSS CNTRL AND SRN PORTIONS OF WW AREA. A STRONGLY FORCED CONVECTIVE LINE HAS RAPIDLY EVOLVED OVER THE PAST HALF HOUR ALONG COLD FRONT FROM S-CNTRL AR SWWD INTO SERN TX /SE OF LFK/. CURRENT SURFACE OBSERVATIONS INDICATE THAT PRE-FRONTAL AIR MASS ACROSS LA REMAINS QUITE MOIST WITH DEWPOINTS IN THE MID TO UPPER 60S. MOREOVER...WINNFIELD LA PROFILER SHOWS THAT AMBIENT KINEMATIC ENVIRONMENT IS STRONGLY SHEARED WITH 50-60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 200-300 M2/S2. GIVEN THE PROMINENT LINEAR CONVECTIVE MODE ALONG FRONT...IT APPEARS THAT DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT AS STORMS CONTINUE SEWD AT 30-35 KTS. HOWEVER...THE STRONG LOW-LEVEL SHEAR DOES SUGGEST SOME POTENTIAL FOR EMBEDDED SUPERCELLS OR LEWP STRUCTURES CAPABLE OF AN ISOLATED TORNADO. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LZK...LCH...SHV...HGX... 32979447 33599173 30589174 29959457 WWWW From Mcd at goshenarc.org Sat Apr 8 04:06:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:06:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080405 SWOMCD SPC MCD 080405 KYZ000-TNZ000-INZ000-ALZ000-MSZ000-ILZ000-MOZ000-ARZ000-080600- MESOSCALE DISCUSSION 0466 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN AND MIDDLE TN / WRN AND CNTRL KY / FAR NRN MS CONCERNING...TORNADO WATCH 170... VALID 080405Z - 080600Z LATEST DATA SHOW COMPLEX SURFACE LOW BECOMING BETTER ORGANIZED ATTM OVER THE MO BOOTHEEL. COLD FRONT TRAILING SSW ACROSS ERN AR IS INTENSIFYING IN RESPONSE TO SEWD ACCELERATION AND AMPLIFICATION OF WRN AR UPPER VORT. SEVERAL BOUNDARIES EXTEND GENERALLY ENE FROM THE LOW...WITH THE MOST SIGNIFICANT OF THESE FOR SEVERE PURPOSES NOW NEARLY STATIONARY OVER EXTREME SRN KY. CONTINUED E/SE MOTION OF AR VORT AND ASSOCIATED MID LEVEL COOLING/ASCENT SUGGEST THAT TSTMS MAY INCREASE IN COVERAGE DURING THE NEXT SEVERAL HOURS ALONG THE BOUNDARY IN FAR SRN KY/NW TN. OTHERS MAY ALSO FORM SOMEWHAT LATER SWD ALONG COLD FRONT INTO WRN TN. AREA VWP DATA SHOW AMPLE DEEP SHEAR IN PLACE TO SUPPORT SUPERCELLS AND OTHER MODES OF SUSTAINED STORMS. THE PROFILES SHOULD REMAIN STRONG THROUGH EARLY SATURDAY. HOWEVER...AT LOWER LEVELS...THE OBSERVED DATA AS WELL AS MODEL FORECAST WINDS SHOW EVIDENCE OF CONVECTIVE MODIFICATION AND BACK-VEER PATTERNS WITH HEIGHT. THESE TENDENCIES SHOULD INCREASE WITH TIME AND SUGGEST THAT THE THREAT FOR TORNADOES WILL CONTINUE TO DIMINISH IN WW 170...ESPECIALLY IN SW TN AND NW MS. NEVERTHELESS...WITH APPROACH OF UPPER VORT...A THREAT FOR HAIL AND POSSIBLY DAMAGING WIND LIKELY WILL PERSIST INTO EARLY SATURDAY. ..CORFIDI.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG... 36469030 35229040 33999025 34728802 35748515 37078497 38268533 WWWW From Mcd at goshenarc.org Sat Apr 8 04:11:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:11:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080407 SWOMCD SPC MCD 080406 VAZ000-WVZ000-080500- MESOSCALE DISCUSSION 0467 NWS STORM PREDICTION CENTER NORMAN OK 1106 PM CDT FRI APR 07 2006 AREAS AFFECTED...SOUTHERN WV/SOUTHWEST VA CONCERNING...SEVERE THUNDERSTORM WATCH 166...168... VALID 080406Z - 080500Z PRIMARY SHORT TERM SEVERE THREAT CONTINUES MAINLY ACROSS THE FAR SOUTHERN PORTIONS OF SEVERE WATCHES 166/168 ACROSS SOUTHWEST VA. OTHERWISE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. STRONGEST STORMS ACROSS SEVERE WATCHES 166/168 ARE OCCURRING ACROSS SOUTHWEST VA IN AREAS SOUTH/SOUTHWEST OF BLACKSBURG AND ROANOKE. THIS ACTIVITY IS FOCUSED ALONG/SOUTH OF CONVECTIVE REINFORCED BOUNDARY...WITH AN UNSTABLE SOUTHWESTLY FEED STILL IMPINGING ON THIS BOUNDARY. SIMILAR TO CURRENT TRENDS...PRIMARY SEVERE THREAT WILL REMAIN FOCUSED ACROSS FAR SOUTHERN VA OVER THE NEXT HOUR OR SO. OTHERWISE...SEVERE THREAT WILL CONTINUE TO DIMINISH REMAINDER OF THE NIGHT...AND SEVERE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AT/BY SCHEDULED 05Z EXPIRATIONS ACCORDINGLY. ..GUYER.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK...RLX...MRX... 37658164 38037971 37387842 36707865 36637983 36748121 37048190 WWWW From Mcd at goshenarc.org Sat Apr 8 04:12:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:12:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080355 SWOMCD SPC MCD 080355 LAZ000-ARZ000-TXZ000-080530- MESOSCALE DISCUSSION 0465 NWS STORM PREDICTION CENTER NORMAN OK 1055 PM CDT FRI APR 07 2006 AREAS AFFECTED...FAR ERN TX INTO WRN AND CNTRL LA CONCERNING...TORNADO WATCH 167... VALID 080355Z - 080530Z THROUGH 06Z...POTENTIAL FOR MAINLY DAMAGING WINDS WILL EXIST ACROSS CNTRL AND SRN PORTIONS OF WW AREA. A STRONGLY FORCED CONVECTIVE LINE HAS RAPIDLY EVOLVED OVER THE PAST HALF HOUR ALONG COLD FRONT FROM S-CNTRL AR SWWD INTO SERN TX /SE OF LFK/. CURRENT SURFACE OBSERVATIONS INDICATE THAT PRE-FRONTAL AIR MASS ACROSS LA REMAINS QUITE MOIST WITH DEWPOINTS IN THE MID TO UPPER 60S. MOREOVER...WINNFIELD LA PROFILER SHOWS THAT AMBIENT KINEMATIC ENVIRONMENT IS STRONGLY SHEARED WITH 50-60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 200-300 M2/S2. GIVEN THE PROMINENT LINEAR CONVECTIVE MODE ALONG FRONT...IT APPEARS THAT DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT AS STORMS CONTINUE SEWD AT 30-35 KTS. HOWEVER...THE STRONG LOW-LEVEL SHEAR DOES SUGGEST SOME POTENTIAL FOR EMBEDDED SUPERCELLS OR LEWP STRUCTURES CAPABLE OF AN ISOLATED TORNADO. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LZK...LCH...SHV...HGX... 32979447 33599173 30589174 29959457  From Mcd at goshenarc.org Sat Apr 8 04:24:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:24:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080405 SWOMCD SPC MCD 080405 KYZ000-TNZ000-INZ000-ALZ000-MSZ000-ILZ000-MOZ000-ARZ000-080600- MESOSCALE DISCUSSION 0466 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN AND MIDDLE TN / WRN AND CNTRL KY / FAR NRN MS CONCERNING...TORNADO WATCH 170... VALID 080405Z - 080600Z LATEST DATA SHOW COMPLEX SURFACE LOW BECOMING BETTER ORGANIZED ATTM OVER THE MO BOOTHEEL. COLD FRONT TRAILING SSW ACROSS ERN AR IS INTENSIFYING IN RESPONSE TO SEWD ACCELERATION AND AMPLIFICATION OF WRN AR UPPER VORT. SEVERAL BOUNDARIES EXTEND GENERALLY ENE FROM THE LOW...WITH THE MOST SIGNIFICANT OF THESE FOR SEVERE PURPOSES NOW NEARLY STATIONARY OVER EXTREME SRN KY. CONTINUED E/SE MOTION OF AR VORT AND ASSOCIATED MID LEVEL COOLING/ASCENT SUGGEST THAT TSTMS MAY INCREASE IN COVERAGE DURING THE NEXT SEVERAL HOURS ALONG THE BOUNDARY IN FAR SRN KY/NW TN. OTHERS MAY ALSO FORM SOMEWHAT LATER SWD ALONG COLD FRONT INTO WRN TN. AREA VWP DATA SHOW AMPLE DEEP SHEAR IN PLACE TO SUPPORT SUPERCELLS AND OTHER MODES OF SUSTAINED STORMS. THE PROFILES SHOULD REMAIN STRONG THROUGH EARLY SATURDAY. HOWEVER...AT LOWER LEVELS...THE OBSERVED DATA AS WELL AS MODEL FORECAST WINDS SHOW EVIDENCE OF CONVECTIVE MODIFICATION AND BACK-VEER PATTERNS WITH HEIGHT. THESE TENDENCIES SHOULD INCREASE WITH TIME AND SUGGEST THAT THE THREAT FOR TORNADOES WILL CONTINUE TO DIMINISH IN WW 170...ESPECIALLY IN SW TN AND NW MS. NEVERTHELESS...WITH APPROACH OF UPPER VORT...A THREAT FOR HAIL AND POSSIBLY DAMAGING WIND LIKELY WILL PERSIST INTO EARLY SATURDAY. ..CORFIDI.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG... 36469030 35229040 33999025 34728802 35748515 37078497 38268533  From Mcd at goshenarc.org Sat Apr 8 04:24:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:24:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080407 SWOMCD SPC MCD 080406 VAZ000-WVZ000-080500- MESOSCALE DISCUSSION 0467 NWS STORM PREDICTION CENTER NORMAN OK 1106 PM CDT FRI APR 07 2006 AREAS AFFECTED...SOUTHERN WV/SOUTHWEST VA CONCERNING...SEVERE THUNDERSTORM WATCH 166...168... VALID 080406Z - 080500Z PRIMARY SHORT TERM SEVERE THREAT CONTINUES MAINLY ACROSS THE FAR SOUTHERN PORTIONS OF SEVERE WATCHES 166/168 ACROSS SOUTHWEST VA. OTHERWISE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. STRONGEST STORMS ACROSS SEVERE WATCHES 166/168 ARE OCCURRING ACROSS SOUTHWEST VA IN AREAS SOUTH/SOUTHWEST OF BLACKSBURG AND ROANOKE. THIS ACTIVITY IS FOCUSED ALONG/SOUTH OF CONVECTIVE REINFORCED BOUNDARY...WITH AN UNSTABLE SOUTHWESTLY FEED STILL IMPINGING ON THIS BOUNDARY. SIMILAR TO CURRENT TRENDS...PRIMARY SEVERE THREAT WILL REMAIN FOCUSED ACROSS FAR SOUTHERN VA OVER THE NEXT HOUR OR SO. OTHERWISE...SEVERE THREAT WILL CONTINUE TO DIMINISH REMAINDER OF THE NIGHT...AND SEVERE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AT/BY SCHEDULED 05Z EXPIRATIONS ACCORDINGLY. ..GUYER.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK...RLX...MRX... 37658164 38037971 37387842 36707865 36637983 36748121 37048190  From Mcd at goshenarc.org Sat Apr 8 07:32:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 03:32:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080731 SWOMCD SPC MCD 080730 ALZ000-GAZ000-MSZ000-LAZ000-080900- MESOSCALE DISCUSSION 0468 NWS STORM PREDICTION CENTER NORMAN OK 0230 AM CDT SAT APR 08 2006 AREAS AFFECTED...NERN LA/CENTRAL MS/CENTRAL AL CONCERNING...TORNADO WATCH 169... VALID 080730Z - 080900Z SEVERE STORMS CONTINUE MOVING EWD ACROSS SRN PORTIONS OF WW 169. THREAT MAY SPILL S OF WW WITH TIME...POSSIBLY REQUIRING NEW WW ACROSS SRN AL AND PERHAPS SERN MS. VIGOROUS CONVECTION CONTINUES ALONG AND AHEAD OF COLD FRONT NOW CROSSING THE MID MS VALLEY/LA. RAOB FROM JACKSON MS AT 06Z REVEALS CAPE/SHEAR COMBINATION VERY FAVORABLE FOR SEVERE STORMS. THOUGH CAPPING REMAINS AN ISSUE WITH SWD EXTENT -- AS CONFIRMED BY LIMIT TO SWD EXTENSION OF STORMS ALONG FRONT...IT APPEARS THAT SEVERE THREAT MAY SPILL SWD OUT OF WW --- PARTICULARLY ACROSS SRN AL S OF WW. FURTHER...STORMS MAY NOT COMPLETELY VACATE WW ACROSS PORTIONS OF CENTRAL MS/CENTRAL AL BY 09Z -- WHEN WW IS SCHEDULED TO EXPIRE. THEREFORE...NEW WW COULD BE NEEDED FROM SRN PORTIONS OF WW 169 SWD INTO PARTS OF SRN MS/SRN AL. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MOB...JAN...LIX...LCH... 31189195 32759033 34578547 32038519 30619030 30789198 WWWW From Mcd at goshenarc.org Sat Apr 8 07:47:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 03:47:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080746 SWOMCD SPC MCD 080745 NCZ000-SCZ000-GAZ000-080845- MESOSCALE DISCUSSION 0469 NWS STORM PREDICTION CENTER NORMAN OK 0245 AM CDT SAT APR 08 2006 AREAS AFFECTED...NRN GA/WRN SC CONCERNING...TORNADO WATCH 171... VALID 080745Z - 080845Z STORMS CONTINUE MOVING EWD ACROSS WW...THOUGH MOST VIGOROUS STORMS WILL MOVE SEWD INTO WW 172. WW WILL LIKELY BE ALLOWED TO EXPIRE AT 09Z. LATEST RADAR IMAGERY SHOWS STRONGEST CONVECTION -- NOW OVER FAR SERN PORTIONS OF WW -- MOVING SEWD INTO WW 172. MEANWHILE...STORMS FURTHER N INTO NRN GA HAVE SHOWN A SLOW WEAKENING TREND WITH TIME. THIS SEEMS TO CONFIRM LATEST OBJECTIVE ANALYSES...WHICH INDICATE ONLY MARGINAL INSTABILITY AT BEST OVER NRN GA. WITH EVEN LESS UNSTABLE AIRMASS INDICATED INTO THE WRN CAROLINAS...EXPECT STORMS TO CONTINUE WEAKENING AS THEY MOVE EWD. THEREFORE...NEW WW IS NOT ANTICIPATED. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 34238460 34958375 35228230 34248298 33998406 WWWW From Mcd at goshenarc.org Sat Apr 8 11:44:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 07:44:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081142 SWOMCD SPC MCD 081142 GAZ000-ALZ000-081315- MESOSCALE DISCUSSION 0470 NWS STORM PREDICTION CENTER NORMAN OK 0642 AM CDT SAT APR 08 2006 AREAS AFFECTED...CENTRAL GA CONCERNING...TORNADO WATCH 172... VALID 081142Z - 081315Z BROKEN LINE OF THUNDERSTORMS CONTINUE DRIFTING SWD ACROSS THE SRN HALF OF WW WHILE WEAKENING WITH TIME. LIMITED SEVERE THREAT CONTINUES. LATEST RADAR IMAGERY INDICATES A BROKEN LINE OF STORMS -- ALONG THE LEADING EDGE OF A SEWD-MOVING OUTFLOW BOUNDARY -- MOVING ACROSS CENTRAL GA ATTM. THOUGH DEEP-LAYER SHEAR REMAINS SUFFICIENT FOR SEVERE STORMS...MODEL SOUNDINGS AND LATEST OBJECTIVE ANALYSES INDICATE LIMITED INSTABILITY S OF ONGOING STORMS. THOUGH A LIMITED THREAT FOR SEVERE WEATHER -- MAINLY IN THE FORM OF HAIL -- MAY PERSIST FOR THE NEXT HOUR OR TWO...OVERALL CONVECTIVE TRENDS SHOULD REMAIN DOWNWARD. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...FFC...BMX... 32428525 32898399 33478256 32468258 32118523 WWWW From Mcd at goshenarc.org Sat Apr 8 12:31:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 08:31:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081230 SWOMCD SPC MCD 081230 VAZ000-NCZ000-SCZ000-081430- MESOSCALE DISCUSSION 0471 NWS STORM PREDICTION CENTER NORMAN OK 0730 AM CDT SAT APR 08 2006 AREAS AFFECTED...SERN VA/ERN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081230Z - 081430Z SEVERE THREAT -- CURRENTLY LIMITED TO ELEVATED HAIL -- SHOULD INCREASE OVER THE NEXT FEW HOURS AS BOUNDARY LAYER DESTABILIZES. NEW WW MAY BE NEEDED. LATEST RADAR IMAGERY SHOWS AN INCREASE IN CONVECTIVE INTENSITY ACROSS CENTRAL NC ATTM...ABOVE A STABLE BOUNDARY LAYER. INSTABILITY REMAINS LIMITED PER 12Z GSO /GREENSBORO NC/ RAOB...AND THUS WOULD EXPECT ANY SHORT-TERM SEVERE THREAT TO REMAIN IN THE FORM OF MARGINAL HAIL. AS DAYTIME HEATING INTENSIFIES OVER THE NEXT FEW HOURS...EXPECT BOUNDARY LAYER TO SLOWLY DESTABILIZE. WITH SHEAR QUITE FAVORABLE FOR SEVERE STORMS -- AIDED BY 80-PLUS KT MID-LEVEL JET...ANY SURFACE-BASED CONVECTION WOULD LIKELY POSE A THREAT FOR DAMAGING WINDS. THOUGH EWD EXTENT OF THREAT SHOULD REMAIN LIMITED FOR AT LEAST THE NEXT SEVERAL HOURS GIVEN DRY/STABLE LOWER TROPOSPHERE AS REVEALED BY MORNING MHX /MOREHEAD CITY NC/...A CORRIDOR OF SURFACE-BASED SEVERE THREAT MAY EVOLVE FROM THE COASTAL PLAIN OF NC INTO SERN VA. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CAE... 37227835 37867661 36977612 35677683 34447844 34377996 35937930 WWWW From Mcd at goshenarc.org Sat Apr 8 13:38:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 09:38:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081337 SWOMCD SPC MCD 081337 GAZ000-FLZ000-ALZ000-081530- MESOSCALE DISCUSSION 0472 NWS STORM PREDICTION CENTER NORMAN OK 0837 AM CDT SAT APR 08 2006 AREAS AFFECTED...SRN AL...WRN AND CNTRL FL PANHANDLE THROUGH SRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081337Z - 081530Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY NEXT FEW HOURS FROM SRN AL...SRN GA AND INTO THE WRN FL PANHANDLE AND SUBSEQUENTLY SPREAD EWD. SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL AND ISOLATED TORNADOES WILL BE THE PRIMARY THREATS. ISOLATED DAMAGING WIND GUSTS MAY ALSO OCCUR. TORNADO WATCH WILL BE ISSUED SHORTLY. EARLY THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM THE CAROLINAS SWWD THROUGH CNTRL GA AND FARTHER SWWD THROUGH SRN AL. THE WARM SECTOR S OF THIS BOUNDARY IS MOIST WITH BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S. THE ATMOSPHERE IS ALREADY MODERATELY UNSTABLE WITH MLCAPE ON THE ORDER OF 2000 J/KG AND FURTHER DESTABILIZATION WILL OCCUR AS HEATING COMMENCES. STORMS SHOULD CONTINUE DEVELOPING ALONG AND AHEAD OF OUTFLOW BOUNDARY. A WSWLY 40 KT LOW LEVEL JET WILL PERSIST IN THIS REGION WITHIN A ZONE OF HEIGHT FALLS DOWNSTREAM FROM A SEWD MOVING SHORTWAVE TROUGH. DEEP LAYER SHEAR ON THE ORDER OF 50 KT AND FAVORABLE LOW LEVEL HODOGRAPHS WILL SUPPORT SUPERCELLS WITH LOW LEVEL MESOCYCLONES CAPABLE PRODUCING LARGE HAIL AND TORNADOES. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAX...FFC...TAE...BMX...MOB... 31288694 32178536 32458282 31778238 30678317 29828496 30508607 30388752 WWWW From Mcd at goshenarc.org Sat Apr 8 16:02:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 12:02:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081601 SWOMCD SPC MCD 081600 GAZ000-FLZ000-081800- MESOSCALE DISCUSSION 0473 NWS STORM PREDICTION CENTER NORMAN OK 1100 AM CDT SAT APR 08 2006 AREAS AFFECTED...SERN GA THROUGH PORTIONS OF NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081600Z - 081800Z THUNDERSTORMS ARE EXPECTED TO DEVELOP AND SPREAD EWD THROUGH SERN GA AND PORTIONS OF NRN FL BY MID AFTERNOON. A FEW SEVERE STORMS INCLUDING SUPERCELLS WILL BE POSSIBLE. A WW MAY BE NEEDED FOR THIS AREA WITHIN THE NEXT COUPLE HOURS. LATE THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM ERN SC SWWD THROUGH S CNTRL GA AND FARTHER SW INTO SERN AL. THIS BOUNDARY IS MOVING SLOWLY SEWD. THE WARM SECTOR S OF THIS BOUNDARY IS MODERATELY UNSTABLE WITH MLCAPE FROM 1000 TO 1500 J/KG ACROSS SERN GA AND NRN FL. STRONG SURFACE HEATING OF THE MOIST BOUNDARY LAYER WILL PROMOTE FURTHER DESTABILIZATION INTO THE AFTERNOON. THE MORNING RAOB DATA FROM JACKSONVILLE SHOWED PRESENCE OF A MID LEVEL INVERSION...AND THIS MAY TEND TO INHIBIT DEEP ROBUST CONVECTION A WHILE LONGER. HOWEVER...HEIGHT FALLS AND DEEPER LAYER ASCENT ASSOCIATED WITH AN UPSTREAM SHORTWAVE TROUGH WILL SPREAD SEWD. THIS SHOULD CONTRIBUTE TO THERMODYNAMIC PROFILES MORE CONDUCIVE FOR THUNDERSTORMS THIS AFTERNOON. MID LEVEL JET ON SERN PERIPHERY OF UPPER TROUGH WILL SHIFT SEWD ABOVE THE WSWLY LOW LEVEL JET AND MAINTAIN FAVORABLE VERTICAL SHEAR PROFILES FOR ORGANIZED STORMS INCLUDING SUPERCELLS. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...JAX...FFC... 30128159 29978282 32168297 32398130 31228147 WWWW From Mcd at goshenarc.org Sat Apr 8 17:40:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 13:40:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081739 SWOMCD SPC MCD 081738 NCZ000-081945- MESOSCALE DISCUSSION 0474 NWS STORM PREDICTION CENTER NORMAN OK 1238 PM CDT SAT APR 08 2006 AREAS AFFECTED...ERN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081738Z - 081945Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY ACROSS COASTAL NC THIS AFTERNOON. POTENTIAL WILL EXIST FOR ORGANIZED SEVERE STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOWS. AREA IS BEING MONITORED FOR A POSSIBLE WW. EARLY THIS AFTERNOON A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM NEAR ELIZABETH CITY SWWD THROUGH ERN SC. A PRE-FRONTAL CONVERGENCE ZONE EXISTS W OF THIS BOUNDARY ACROSS ERN NC FROM NEAR ROCKY MOUNT SWWD TO JUST E OF FLORENCE IN ERN SC. THE ATMOSPHERE IN THE VICINITY OF THESE BOUNDARIES IS DESTABILIZING WITH MLCAPE FROM 500 TO 1000 J/KG. CONVECTIVE INHIBITION APPEARS TO HAVE WEAKENED SUFFICIENTLY TO PROMOTE THUNDERSTORM DEVELOPMENT. THE BEST CHANCE FOR INITIATION APPEARS TO BE ALONG THE OUTFLOW BOUNDARY NEAR COASTAL NC WHERE CONVERGENCE COULD BE LOCALLY ENHANCED BY SEA BREEZE CIRCULATIONS. STRONG LOW LEVEL AND DEEP LAYER SHEAR PROFILES WILL BE SUPPORTIVE OF ORGANIZED STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM... 34327765 34027828 33997867 34277870 34807814 35597741 36307672 36287594 35477584 WWWW From Mcd at goshenarc.org Sat Apr 8 19:01:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 15:01:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081900 SWOMCD SPC MCD 081900 GAZ000-FLZ000-ALZ000-082100- MESOSCALE DISCUSSION 0475 NWS STORM PREDICTION CENTER NORMAN OK 0200 PM CDT SAT APR 08 2006 AREAS AFFECTED...SERN AL...THE WRN AND CNTRL FL PANHANDLE THROUGH SWRN GA CONCERNING...TORNADO WATCH 173... VALID 081900Z - 082100Z THREAT FOR SEVERE STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS WILL CONTINUE NEXT SEVERAL HOURS. LARGE HAIL...DAMAGING WIND GUSTS AND ISOLATED TORNADOES REMAIN POSSIBLE WITH THE STRONGER STORMS. THIS AFTERNOON A SEWD MOVING OUTFLOW BOUNDARY EXTENDS ACROSS SRN GA INTO SERN AL. MODERATE INSTABILITY EXISTS IN WARM SECTOR S OF THIS BOUNDARY...AND STORMS HAVE INTENSIFIED DURING THE LAST HOUR AS DESTABILIZATION INCREASES. VERTICAL SHEAR PROFILES ARE LARGELY UNIDIRECTIONAL SWLY WITH 0-6 KM SHEAR ON THE ORDER OF 45 KT. STRONGEST LOW LEVEL SHEAR EXISTS OVER SRN GA AND THE FL PANHANDLE WHERE THE SURFACE FLOW REMAINS BACKED TO A MORE SLY DIRECTION. POTENTIAL FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOW ECHOES WILL CONTINUE THROUGH THE AFTERNOON. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB... 30098346 29538669 30968661 31608520 31548322 WWWW From Mcd at goshenarc.org Sat Apr 8 20:23:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 16:23:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082022 SWOMCD SPC MCD 082022 SCZ000-GAZ000-FLZ000-082215- MESOSCALE DISCUSSION 0476 NWS STORM PREDICTION CENTER NORMAN OK 0322 PM CDT SAT APR 08 2006 AREAS AFFECTED...SERN GA EXTREME ERN SC THROUGH NRN FL CONCERNING...TORNADO WATCH 174... VALID 082022Z - 082215Z THREAT FOR LARGE HAIL...ISOLATED TORNADOES AND DAMAGING WIND WILL PERSIST ACROSS SRN GA INTO NRN FL INTO THE EARLY EVENING. THE THREAT ACROSS ERN SC WILL END WITHIN ANOTHER 1-2 HOURS AS THE STORMS MOVE OFFSHORE. STORMS WILL CONTINUE DEVELOPING ALONG AND AHEAD OF SEWD ADVANCING OUTFLOW BOUNDARY ACROSS SRN GA INTO NRN FL NEXT SEVERAL HOURS. THE LATEST RUC FORECASTS A 40 KT WSWLY LOW LEVEL JET WILL PERSIST INTO THE EARLY EVENING OVER NRN FL AND EXTREME SRN GA WITHIN A ZONE OF HEIGHT FALLS ASSOCIATED WITH SEWD ADVANCING SHORTWAVE TROUGH. VWP DATA ACROSS EXTREME SRN GA CONTINUE TO SHOW 0-1 KM STORM RELATIVE HELICITY AROUND 180 M2/S2 FOR ENEWD MOVING STORMS AND DEEP LAYER SHEAR ON THE ORDER OF 50 KT. ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOW ECHOES REMAIN LIKELY WITHIN THIS ENVIRONMENT. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILM...CHS...JAX...TAE... 33227871 32278001 30988138 29768126 29578327 31248308 32328148 33847909 WWWW From Mcd at goshenarc.org Sat Apr 8 21:35:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 17:35:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082134 SWOMCD SPC MCD 082134 NCZ000-082300- MESOSCALE DISCUSSION 0477 NWS STORM PREDICTION CENTER NORMAN OK 0434 PM CDT SAT APR 08 2006 AREAS AFFECTED...FAR ERN NC AND ADJACENT COASTAL WATERS CONCERNING...SEVERE THUNDERSTORM WATCH 175... VALID 082134Z - 082300Z THREAT FOR ISOLATED LARGE HAIL AND DAMAGING WINDS WILL PERSIST ALONG THE ERN NC OUTER BANKS AND ADJACENT COASTAL WATERS FOR THE NEXT 1-2 HOURS. OVERALL SEVERE THREAT WILL CONTINUE TO DIMINISH ACROSS WW 175. STORMS OVER ERN NC HAVE CONSOLIDATED INTO A LINEAR CLUSTER FROM AROUND NCA TO FFA. THIS LINE SHOULD CONTINUE TO MOVE NEWD ACROSS THE OUTER BANKS AND OFFSHORE. 0-6 KM SHEAR VALUES AROUND 70KT PER MHX VAD PROFILER MAY STILL SUPPORT STRONG WINDS BUT INCREASING BOUNDARY LAYER STABILIZATION WILL DIMINISH THE DAMAGING WIND THREAT. FURTHER SOUTH...ADDITIONAL DISCRETE DEVELOPMENT IS STILL POSSIBLE WITH MUCAPES ON THE ORDER OF AROUND 1000 J/KG. COMBINED WITH THE STRONG SHEAR...MARGINALLY SEVERE HAIL POTENTIAL WILL STILL EXIST FOR THE NEXT FEW HOURS ALONG THE OUTER BANKS. ..GRAMS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...ILM... 33977796 34487760 35177699 35737619 36047577 36097536 35627511 35247523 35017546 34347654 34027733 33467798 33437840 33677853 WWWW From Mcd at goshenarc.org Sat Apr 8 23:01:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 19:01:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082300 SWOMCD SPC MCD 082259 FLZ000-GAZ000-090030- MESOSCALE DISCUSSION 0478 NWS STORM PREDICTION CENTER NORMAN OK 0559 PM CDT SAT APR 08 2006 AREAS AFFECTED...NRN FL INTO N CNTRL FL PENINSULA CONCERNING...TORNADO WATCH 174...176... VALID 082259Z - 090030Z CONTINUE REMAINING VALID PORTIONS OF WW. ISOLATED SEVERE THREAT MAY DEVELOP INTO NORTH CENTRAL PENINSULA AREAS SOUTH OF WW 174 SHORTLY. HOWEVER...RISK MAY REMAIN MARGINAL ENOUGH TO PRECLUDE THE NEED FOR AN ADDITIONAL WW...AS BELT OF STRONGER FLOW BEGINS TO SHIFT AWAY FROM SOUTH ATLANTIC COASTAL AREAS. TONGUE OF 70F+ DEW POINTS ASSOCIATED WITH BETTER MOIST RETURN FLOW IS READILY EVIDENT IN SURFACE DATA ACROSS THE EASTERN GULF OF MEXICO. THIS EXTENDS THROUGH AREAS NEAR/EAST OF THE FLORIDA BIG BEND INTO SOUTHWARD ADVANCING CONVECTIVE OUTFLOW ACROSS EXTREME SOUTHERN GEORGIA. FORCING ASSOCIATED WITH APPROACHING SOUTHERN BRANCH TROUGH CONTINUES TO AID VIGOROUS CONVECTIVE DEVELOPMENT ALONG OUTFLOW...AND IN WEAK WARM ADVECTION REGIME NOW BEGINNING TO DEVELOP OFF THE NORTHEAST GULF OF MEXICO INTO THE NORTHERN FLORIDA PENINSULA. CONVECTIVE OUTFLOW WILL ADVANCE ACROSS JACKSONVILLE AND THE INTERSTATE 10 CORRIDOR BETWEEN NOW AND 00-01Z...WITH SEVERE THREAT DIMINISHING TO THE NORTH OF BOUNDARY. GUSTY WINDS/LARGE HAIL MAY CONTINUE IN STRONGER CONVECTION ALONG/AHEAD OF BOUNDARY...AND IN NEW DEVELOPMENT ONGOING ALONG EASTERN GULF LOW-LEVEL CONFLUENT ZONE...WHICH WILL GRADUALLY SHIFT INTO COASTAL AREAS FROM NEAR CEDAR KEY THROUGH THE TAMPA AREA THROUGH EARLY EVENING. ..KERR.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TBW...JAX...TAE... 29428446 29858439 30848355 31108253 31168182 31188136 30848074 30138092 29568151 29048189 28618237 28168339 28318395 28778409 29118403 WWWW From Mcd at goshenarc.org Sun Apr 9 14:31:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 10:31:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 091430 SWOMCD SPC MCD 091430 FLZ000-091630- MESOSCALE DISCUSSION 0479 NWS STORM PREDICTION CENTER NORMAN OK 0930 AM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 091430Z - 091630Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY INTO THE AFTERNOON. PRIMARY THREATS WILL BE ISOLATED LARGE HAIL AND DAMAGING WIND GUSTS. WW MAY BE NEEDED FOR PORTIONS OF S FL WITHIN THE NEXT TWO HOURS. LATE THIS MORNING A PRE-FRONTAL SURFACE BOUNDARY EXTENDS ACROSS S CNTRL FL FROM S OF VERO BEACH SWWD TO NEAR FORT MYERS. RICH LOW LEVEL MOISTURE EXISTS IN THE WARM SECTOR BOUNDARY LAYER WITH DEWPOINTS IN THE 70S. THE 12Z RAOB FROM MIAMI SHOWS STEEP MID LEVEL LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER...CONTRIBUTING TO MODERATE INSTABILITY. FURTHER DESTABILIZATION WILL OCCUR AS ANVIL CIRRUS DISSIPATES WITH MLCAPE FROM 2000 TO 2500 J/KG EXPECTED. THE WEAK CAP...DIFFERENTIAL SURFACE HEATING...PRESENCE OF SUBTLE OUTFLOW BOUNDARIES AND POTENTIAL FOR SEA BREEZE CIRCULATIONS WILL CONTRIBUTE TO CONVECTIVE INITIATION INTO THE AFTERNOON. AMBIENT LOW LEVEL FLOW THROUGH 2 KM IS QUITE WEAK AND KINEMATIC PROFILES THROUGH A DEEPER LAYER ARE SUPPORTIVE OF MOSTLY MULTICELLS. HOWEVER...THE THERMODYNAMIC ENVIRONMENT IS FAVORABLE FOR LARGE HAIL WITHIN THE STRONGER STORMS. ..DIAL.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB... 25938015 25338048 25258092 26278145 26828111 27108030 26848006 WWWW From Mcd at goshenarc.org Sun Apr 9 19:44:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 15:44:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 091943 SWOMCD SPC MCD 091943 FLZ000-092145- MESOSCALE DISCUSSION 0480 NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FL CONCERNING...SEVERE THUNDERSTORM WATCH 177... VALID 091943Z - 092145Z THUNDERSTORMS WILL CONTINUE DEVELOPING OVER PORTIONS OF THE SRN FL PENINSULA THIS AFTERNOON. ISOLATED LARGE HAIL AND DAMAGING WIND WILL REMAIN A THREAT WITH THE STRONGER STORMS. BOUNDARIES...SEVERAL OF WHICH APPEAR TO BE ENHANCED BY SEABREEZE CIRCULATIONS...PERSIST ACROSS THE SRN FL PENINSULA. ONE SUCH BOUNDARY EXTENDS FROM NEAR SARASOTA SEWD TO N OF LAKE OKEECHOBEE. OTHER BOUNDARIES EXIST FROM S OF LAKE OKEECHOBEE TO NEAR MIAMI. THE ATMOSPHERE REMAINS MODERATELY UNSTABLE WITH MINIMAL CAP...AND STORMS SHOULD CONTINUE DEVELOPING NEXT FEW HOURS. VERTICAL SHEAR PROFILES ARE WLY UNIDIRECTIONAL...GENERALLY AOB 25 KT AND SUPPORTIVE OF MULTICELLS. ACTIVITY MAY REMAIN MORE LIMITED OVER THE SWRN FL PENINSULA WHERE SURFACE HEATING HAS BEEN MODERATED BY ANVIL DEBRIS. ALSO DEWPOINTS HAVE BEEN IN THE PROCESS OF MIXING DOWNWARD SIGNIFICANTLY ALONG PORTIONS OF THE SWRN COAST...POSSIBLY DUE IN PART TO THE INFLUENCE OF CONVECTIVE OUTFLOW FROM THE OFFSHORE MCS. ..DIAL.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...TBW... 25988012 25458039 25528076 26588149 27228244 27488214 27238134 27418041 26878011 WWWW From Mcd at goshenarc.org Sun Apr 9 22:42:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 18:42:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 092241 SWOMCD SPC MCD 092241 FLZ000-092315- MESOSCALE DISCUSSION 0481 NWS STORM PREDICTION CENTER NORMAN OK 0541 PM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FLORIDA CONCERNING...SEVERE THUNDERSTORM WATCH 177... VALID 092241Z - 092315Z WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 23Z. STRONGER MID-LEVEL FORCING...ASSOCIATED WITH WEAK IMPULSE EMBEDDED WITHIN BROADER SCALE UPPER TROUGHING WHICH ENCOMPASSES MUCH OF THE SOUTHEASTERN STATES AND EASTERN GULF OF MEXICO...APPEARS TO BE SHIFTING EAST OF THE SOUTHERN FLORIDA PENINSULA. LINGERING LOW-LEVEL CONVERGENCE NEAR SYNOPTIC FRONT...SOUTH OF VERO BEACH/TAMPA...REMAINS A FOCUS FOR CONVECTIVE DEVELOPMENT. HOWEVER...COOLING/DRYING OF BOUNDARY LAYER HAS ALREADY OCCURRED ACROSS MUCH OF THE SOUTHERN PENINSULA...AND POTENTIAL FOR ADDITIONAL SEVERE THUNDERSTORMS BEFORE NIGHTFALL SEEMS LIMITED IN SHEAR REGIME ONLY MARGINALLY SUPPORTIVE OF UPDRAFT ROTATION. ..KERR.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...EYW...TBW... 27058243 27288198 27508112 27608026 27757984 27137948 25807972 24758014 24218150 23878170 23548178 23608296 24178316 24818311 25028206 25218153 25588185 26088226 26498254 26658252 WWWW From Mcd at goshenarc.org Mon Apr 10 22:51:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 10 Apr 2006 18:51:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 102249 SWOMCD SPC MCD 102249 SDZ000-NDZ000-MTZ000-110015- MESOSCALE DISCUSSION 0482 NWS STORM PREDICTION CENTER NORMAN OK 0549 PM CDT MON APR 10 2006 AREAS AFFECTED...WRN DAKOTAS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 102249Z - 110015Z VISIBLE IMAGERY SUGGESTS RATHER VIGOROUS CONVECTIVE DEVELOPMENT IS UNDERWAY ACROSS THE NORTHERN HIGH PLAINS...NORTH OF REDIG SD. THIS APPEARS TO HAVE BEEN AIDED BY MID-LEVEL COOLING/LIFT ASSOCIATED WITH SHORT WAVE TROUGH LIFTING NORTHEAST OF THE NORTH CENTRAL ROCKIES THIS AFTERNOON. STRONGEST LARGE-SCALE ASCENT AND STEEPENING LAPSE RATES HAVE BECOME FOCUSED NEAR DEVELOPING SURFACE LOW...WHICH IS PROGGED TO MIGRATE OUT OF SOUTHEAST MONTANA INTO SOUTHWESTERN NORTH DAKOTA BY 02-03Z. THOUGH LOW-LEVEL MOISTURE IS LIMITED...WITH SURFACE DEW POINTS ONLY IN THE LOWER 40S...RUC INDICATES MOST UNSTABLE CAPE FOR HEATED SURFACE-BASED PARCELS MAY BE AS HIGH AS 1000 J/KG. EMBEDDED WITHIN MODERATELY SHEARED ENVIRONMENT...MARGINALLY SUPPORTIVE OF UPDRAFT ROTATION...ISOLATED STRONGER STORMS COULD PRODUCE HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS. MAIN SEVERE THREAT...HOWEVER...MAY BE POTENTIAL FOR DOWNBURSTS AND STRONG GUSTY SURFACE WINDS IN DRY DEEP MIXED BOUNDARY LAYER. ADDITIONAL ISOLATED STORMS MAY DEVELOP OFF THE BLACK HILLS THROUGH EARLY EVENING...BEFORE CONVECTIVE POTENTIAL DIMINISHES FAIRLY QUICKLY AFTER DARK WITH LOSS OF DAYTIME HEATING. ..KERR.. 04/10/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ABR...BIS...UNR...BYZ...GGW... 45880421 46660404 47040378 47380278 46850146 46130175 45000217 44500175 43830229 43960328 44570374 44920392 WWWW From Mcd at goshenarc.org Tue Apr 11 23:00:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 11 Apr 2006 19:00:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 112259 SWOMCD SPC MCD 112258 IAZ000-MOZ000-KSZ000-NEZ000-120030- MESOSCALE DISCUSSION 0483 NWS STORM PREDICTION CENTER NORMAN OK 0558 PM CDT TUE APR 11 2006 AREAS AFFECTED...NE KS...SE NEB...SW IA...NW MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 112258Z - 120030Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. CONVECTIVE INITIATION IS UNDERWAY EAST OF CONCORDIA KS INTO THE BEATRICE NEB AREA...WHERE 80 KT 500 MB JET STREAK IS ENHANCING FORCING FOR UPWARD VERTICAL MOTION AHEAD OF EASTWARD ADVANCING SURFACE FRONT. PRE-FRONTAL LOW-LEVEL THERMAL RIDGE AXIS HAS BECOME FOCUS FOR DESTABILIZATION THIS AFTERNOON...WITH SURFACE TEMPERATURES INCREASING INTO THE LOWER/MID 80S AS DEW POINTS CLIMBED TO NEAR 50F. THIS APPEARS TO BE SUPPORTING CAPE AROUND 750 J/KG AS CAP IS BROKEN. INSTABILITY MAY BE SUFFICIENT TO SUPPORT HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS AS BROKEN LINE OF STORMS CONTINUES TO EVOLVE IN FAVORABLY SHEARED ENVIRONMENT. HOWEVER...RISK OF DAMAGING WIND GUSTS MAY BE PRIMARY SEVERE THREAT. EVAPORATIVE COOLING IN DRY...DEEP MIXED BOUNDARY LAYER PROBABLY WILL ENHANCE DOWNDRAFTS...AND DOWNWARD TRANSFER OF MOMENTUM ASSOCIATED WITH BELT OF 40 TO 50 KT MEAN CLOUD BEARING LAYER FLOW ACCOMPANYING UPPER JET. ISOLATED DAMAGING WIND POTENTIAL SHOULD DIMINISH BY 02-03Z AS BOUNDARY LAYER BEGINS TO COOL/STABILIZE. ..KERR.. 04/11/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP... 40719629 41319578 41869565 42519523 42539423 41759382 40659474 39909535 39399609 39039673 39199713 39879704 WWWW From Mcd at goshenarc.org Wed Apr 12 02:51:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 11 Apr 2006 22:51:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 120249 SWOMCD SPC MCD 120249 ILZ000-IAZ000-WIZ000-MOZ000-KSZ000-120415- MESOSCALE DISCUSSION 0484 NWS STORM PREDICTION CENTER NORMAN OK 0949 PM CDT TUE APR 11 2006 AREAS AFFECTED...ERN IA...PARTS OF NRN MO...SW WI...NW IL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 120249Z - 120415Z SEVERE POTENTIAL IS EXPECTED TO DIMINISH NEXT FEW HOURS. FORCING IN EXIT REGION OF CYCLONIC MID-LEVEL JET STREAK...FOCUSED ALONG/AHEAD OF WEAKENING SURFACE LOW/COLD FRONT...HAS PROGRESSED THROUGH NARROW TONGUE OF STRONGER SURFACE BASED INSTABILITY...WHERE LAPSE RATES BECAME QUITE STEEP THIS AFTERNOON WITH DAYTIME HEATING. THOUGH RUC GUIDANCE SUGGESTS UPPER SPEED MAXIMUM IS WEAKENING...MID- LEVEL COOLING/LIFT MAY MAINTAIN SUFFICIENT DESTABILIZATION FOR CONTINUATION OF THUNDERSTORM ACTIVITY EASTWARD ACROSS THE REMAINDER OF IOWA/NORTHERN MISSOURI BY 06Z. RELATIVE HUMIDITIES BELOW CLOUD BASES LIKELY WILL REMAIN SUFFICIENTLY LOW TO ENHANCE DOWNDRAFTS... AND SOME RISK FOR GUSTY SURFACE WINDS...BUT THIS SEEMS LIKELY TO BECOME MORE SPORADIC IN COOLER/COOLING BOUNDARY LAYER. POTENTIAL FOR MARGINALLY SEVERE HAIL WILL ALSO DROP OFF IN COOLER LOW-LEVEL ENVIRONMENT WITH WEAKER LAPSE RATES IN CLOSER PROXIMITY TO THE MISSISSIPPI RIVER. ..KERR.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...ARX...DMX...EAX...TOP... 42329329 43379286 43249109 43059089 42349053 41579058 40879081 40439123 39479224 38849372 38199599 39479474 40299390 41059332 WWWW From Mcd at goshenarc.org Wed Apr 12 17:37:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 13:37:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 121735 SWOMCD SPC MCD 121735 OHZ000-MIZ000-INZ000-122000- MESOSCALE DISCUSSION 0485 NWS STORM PREDICTION CENTER NORMAN OK 1235 PM CDT WED APR 12 2006 AREAS AFFECTED...EXTREME SERN LWR MI...EXTREME NERN IND...NRN/CNTRL OH CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 121735Z - 122000Z TSTMS WILL DEVELOP SWD FROM SRN LWR MI INTO EXTREME NERN IND EARLY THIS AFTN...THEN MOVE EWD AND BECOME STRONGER IN NRN/CNTRL OH AFTER 21Z. A FEW STORMS MAY PRODUCE DAMAGING WINDS...LARGE HAIL AND PERHAPS AN ISOLD TORNADO AND A WW MAY BE NEEDED WITHIN THE HOUR. WELL-DEFINED UPPER VORTICITY CENTER WAS MOVING ACROSS LWR MI AT 30 KTS AND WILL BE OVER SWRN ONTARIO BY 22Z. TRAILING TROUGH PASSED THE WLC INDIANA PROFILER AROUND 15Z AND WILL SWING EWD ACROSS SERN LWR MI AND NRN/CNTRL OH THROUGH EARLY EVENING. CORRESPONDING SFC REFLECTION...IN THE FORM OF CONVERGENCE...WILL BE THE IMPETUS FOR TSTM INITIATION FROM SCNTRL/SERN LWR MI INTO NERN IND EARLY THIS AFTN. MESOANALYSIS SHOWS A TONGUE OF 50-55 DEGREE F DEW POINTS ADVECTING NEWD AHEAD OF THE FRONT COINCIDENT WITH THE STEEPEST LOW-LEVEL LAPSE RATES. THIS WILL BE SUFFICIENT TO SUPPORT TSTMS ALONG/AHEAD OF THE FRONT THIS AFTN. TAMDAR/ACAR SOUNDINGS FROM KTOL/KDTW EXHIBIT VERY STRONG LOW-LEVEL WIND FIELDS WITH 45+ KTS JUST OFF THE SFC...WITH FLOW TURNING WNWLY ABOVE 3 KM. THIS IS BOOSTING VERTICAL AND LOW-LEVEL SHEAR VALUES TO SUPPORT BRIEF SUPERCELL STRUCTURES. MEAN-SHEAR VECTORS IN THE 2-6KM LAYER NEARLY NORMAL TO THE INITIATING BOUNDARY SUGGESTS THAT THERE COULD BE DISCRETE STRUCTURES. BUT...EVOLUTION INTO A MIX OF LINEAR AND DISCRETE CELLS WILL BE LIKELY OWING TO STRONG FORCING. STRONGER STORMS WILL BE CAPABLE OF LARGE HAIL GIVEN STEEP MID-LEVEL LAPSE RATES...AND DAMAGING WINDS WILL BE LIKELY. ISOLD TORNADOES CANNOT BE RULED OUT GIVEN THE MAGNITUDE OF LOW-LEVEL SHEAR. ..RACY.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PBZ...RLX...CLE...ILN...DTX...IWX...GRR...IND... 40028464 41098545 42288478 42728387 42568300 42148184 41658115 40728064 39948188 39768301 39718411 WWWW From Mcd at goshenarc.org Wed Apr 12 20:06:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 16:06:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122004 SWOMCD SPC MCD 122004 ARZ000-MOZ000-OKZ000-122200- MESOSCALE DISCUSSION 0486 NWS STORM PREDICTION CENTER NORMAN OK 0304 PM CDT WED APR 12 2006 AREAS AFFECTED...EXTREME SRN MO...EXTREME NERN OK...NRN AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122004Z - 122200Z SFC ANALYSIS PLACES AN E-W ORIENTED BOUNDARY ACROSS NRN OK AND AR. WEAK CONVERGENCE ALONG THE FRONT...AND STRONG BOUNDARY LAYER HEATING HAS BEEN SUFFICIENT FOR ISOLD TSTM INITIATION ACROSS NRN AR. VSBL SATL SHOWS ADDITIONAL CUMULUS GROWING THE LENGTH OF THE FRONT FROM EAST OF KTUL TO JUST WEST OF THE MO BOOTHEEL. THOUGH THE FLOW IN THE BOUNDARY LAYER-3KM LAYER IS WEAK...STRONGER FLOW EXISTS ABOVE...BOOSTING 6KM SHEAR INTO THE 30-35 KT RANGE. THIS SUGGESTS THAT MAINLY ISOLD MULTICELL STORMS WILL EXIST WITH SLOW STORM MOTION TO THE SOUTHEAST AROUND 20 KTS. NONETHELESS...SHALLOW INVERTED-V STRUCTURE IN THE BOUNDARY LAYER AND STEEP LAPSE RATES ABOVE WILL BE SUFFICIENT FOR GUSTY WINDS AND PERHAPS MARGINALLY SEVERE HAIL. ..RACY.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF...TSA... 36669435 36539360 36319211 36129134 35679149 35559231 35659331 36139504 WWWW From Mcd at goshenarc.org Wed Apr 12 21:06:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 17:06:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122104 SWOMCD SPC MCD 122104 TXZ000-122330- MESOSCALE DISCUSSION 0487 NWS STORM PREDICTION CENTER NORMAN OK 0404 PM CDT WED APR 12 2006 AREAS AFFECTED...WRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122104Z - 122330Z PREDOMINATELY SUB-SEVERE CONVECTION IS EXPECTED TO DEVELOP ACROSS WRN CENTRAL TX THROUGH THE AFTERNOON...WITH LOCALLY STRONG WINDS AND SMALL HAIL POSSIBLE. LATEST VISIBLE IMAGERY INDICATES TCU EXTENDING FROM S OF CDS TO E OF MAF...ALONG SOON TO BE RETREATING DRYLINE AND WITHIN SURFACE PRESSURE TROUGH. ALTHOUGH LOW LEVEL CONVERGENCE IS WEAK...CONTINUED HEATING WILL ALLOW FOR AT LEAST ISOLATED THUNDERSTORMS TO DEVELOP. SHEAR PROFILES ARE WEAK THROUGHOUT THE COLUMN DUE TO UPPER HIGH OVERHEAD. THUS...ONLY PULSE TYPE CONVECTION IS ANTICIPATED. GIVEN 1000-1500 MLCAPE AND RELATIVELY DRY SUB-CLOUD LAYER...STRONG WIND GUSTS...AND EVEN SOME SMALL HAIL MAY OCCUR. ADDITIONAL DEVELOPMENT MAY OCCUR ON ANY OUTFLOW BOUNDARIES THAT DEVELOP...WITH DECREASING THREAT AFTER SUNSET. ..JEWELL.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...SJT...LUB...MAF... 34069952 32529999 31780094 31520127 32440215 33100177 33970118 34390057 34450004 WWWW From Mcd at goshenarc.org Wed Apr 12 22:09:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 18:09:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122208 SWOMCD SPC MCD 122207 PAZ000-NYZ000-WVZ000-OHZ000-122300- MESOSCALE DISCUSSION 0488 NWS STORM PREDICTION CENTER NORMAN OK 0507 PM CDT WED APR 12 2006 AREAS AFFECTED...NERN OH/NWRN PA/FAR WRN NY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122207Z - 122300Z ISOLATED DAMAGING WIND GUSTS AND MARGINALLY SEVERE HAIL WILL BE POSSIBLE THROUGH 00-01Z ACROSS NERN OH/NWRN PA AND POSSIBLY INTO FAR WRN NY. BAND OF STORMS EXTENDING FROM SRN ONTARIO SWWD ACROSS LAKE ERIE TO NORTH CENTRAL OH WILL CONTINUE TO SPREAD EWD AT 45 KT. ALTHOUGH INSTABILITY IS VERY WEAK EAST OF THIS ACTIVITY...SLIGHTLY GREATER INSTABILITY /MLCAPE 500 J/KG/ ACROSS WRN OH/NRN KY IS BEING FED INTO NERN OH PER A 40-50 KT SWLY LLJ. STRONG FORCING SPREADING ACROSS THE LOWER GREAT LAKES/UPPER OH VALLEY REGION AT THIS TIME WILL MAINTAIN ORGANIZED LINEAR STRUCTURE...BUT 40-50 KT EFFECTIVE SHEAR ORIENTED NORMAL TO BAND OF STORMS SHOULD ALSO SUPPORT DISCRETE STRUCTURES. STRONGER CORES WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS... GIVEN STRONG WINDS IN THE LOWER TROPOSPHERE /AROUND 50 KT JUST BELOW 1 KM AGL PER CLE WSR-88D VAD/ AND INVERTED-V THERMODYNAMIC PROFILES /25-35 DEGREE SURFACE DEWPOINT DEPRESSIONS/ FAVORING DOWNWARD MOMENTUM TRANSPORT. MARGINALLY SEVERE HAIL WILL ALSO BE POSSIBLE. HOWEVER...WEAK INSTABILITY IS EXPECTED TO LIMIT OVERALL SEVERE THREAT/COVERAGE. ..PETERS.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BUF...CTP...PBZ...CLE... 41008245 41378166 42088075 42547936 42317906 40917948 40628045 40558209 40598261 WWWW From Mcd at goshenarc.org Thu Apr 13 16:53:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 12:53:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 131651 SWOMCD SPC MCD 131651 VAZ000-131845- MESOSCALE DISCUSSION 0489 NWS STORM PREDICTION CENTER NORMAN OK 1151 AM CDT THU APR 13 2006 AREAS AFFECTED...PARTS OF NW INTO CNTRL VA CONCERNING...CONVECTIVE TRENDS VALID 131651Z - 131845Z DESPITE INCREASING MID-LEVEL SUBSIDENCE ACROSS PARTS OF THE UPPER OHIO VALLEY...THROUGH AND INTO THE LEE OF THE CENTRAL APPALACHIANS ...SURFACE HEATING AND OROGRAPHY HAVE PROVEN SUFFICIENT TO SUPPORT INITIATION OF CONVECTION. THIS IS OCCURRING OFF THE HIGHER TERRAIN TO THE NORTH/NORTHWEST CHARLOTTESVILLE...WHERE MOST UNSTABLE CAPE NOW APPEARS TO BE ON THE ORDER OF 1500 J/KG. EMBEDDED WITHIN MODERATELY STRONG NORTHWESTERLY MID/UPPER FLOW... CONVECTION IS EXPECTED TO PROPAGATE INTO/THROUGH THE CHARLOTTESVILLE AREAS BY 18-19Z...WHEN DEVELOPING STORMS MAY BECOME ROOTED IN A DEEP MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS. HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS MAY OCCUR IN STRONGER CELLS...AND DOWNBURSTS ALSO APPEARS POSSIBLE. HOWEVER... GIVEN LACK OF MORE FAVORABLE MID/UPPER SUPPORT FOR UPWARD VERTICAL MOTION...STRONGER STORMS SEEM LIKELY TO REMAIN ISOLATED...AND ANY SEVERE THREAT RATHER HIGHLY LOCALIZED. ..KERR.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 38767828 38767786 38377751 37857743 37577809 37547856 37257915 37177984 37358002 37657975 38137936 38447912 38667866 WWWW From Mcd at goshenarc.org Thu Apr 13 22:01:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 18:01:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 132159 SWOMCD SPC MCD 132159 WIZ000-ILZ000-IAZ000-MNZ000-140000- MESOSCALE DISCUSSION 0490 NWS STORM PREDICTION CENTER NORMAN OK 0459 PM CDT THU APR 13 2006 AREAS AFFECTED...SERN MN / NERN IA / SWRN WI CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 132159Z - 140000Z MODIFIED TAMDAR/ACARS SOUNDINGS SHOW A NEARLY UNCAPPED ENVIRONMENT WHERE IT HAS HEATED INTO THE UPPER 80S...ALONG LEADING EDGE OF HIGHER SURFACE DEWPOINTS STRETCHING ACROSS CENTRAL IA TOWARD ALO. VISIBLE IMAGERY INDICATED INCREASING CU FIELD ACROSS WRN IA WHERE IT HAS BECOME HOT...WITH RECENT TAMDAR SOUNDING SHOWING VERY DEEP MIXED LAYER EXTENDING TO 700 MB WITH ONLY UPPER 40S DEWPOINTS. ALTHOUGH CU FIELD IS INCREASING OVER W CENTRAL IA...FOCUS FOR DEVELOPMENT REMAINS WEAK...WITH MODEST LOW LEVEL CONVERGENCE WITHIN SURFACE TROUGH. MOST LIKELY AREA FOR DEEP CONVECTIVE INITIATION WILL BE FARTHER NE ALONG WARM FRONT INTO NERN IA/SERN MN/SWRN WI WHERE CONVERGENCE WILL BE STRONGEST AND BENEATH WEAKER CAP. 18Z PARALLEL NAM RUN INDICATES STORMS DEVELOPING AROUND 00Z OVER SERN MN WITH MORE ISOLATED DEVELOPMENT INTO ERN IA. IF THIS OCCURS...A FEW SUPERCELLS WILL BE POSSIBLE GIVEN STRONG SHEAR PROFILES...WITH MAINLY A LARGE HAIL THREAT...TRANSITIONING TO A DAMAGING WIND THREAT WITH TIME AS STORMS EVOLVE SEWD AND COLD POOL GROWS. ..JEWELL.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...LOT...MKX...DVN...ARX...MPX...DMX... 45189142 44719003 43568900 42658884 42038910 41619037 41559125 41739222 42329388 43019448 43579395 43989356 44879314 45079246 WWWW From Mcd at goshenarc.org Thu Apr 13 23:14:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 19:14:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 132312 SWOMCD SPC MCD 132312 NYZ000-PAZ000-140015- MESOSCALE DISCUSSION 0491 NWS STORM PREDICTION CENTER NORMAN OK 0612 PM CDT THU APR 13 2006 AREAS AFFECTED...PARTS OF CENTRAL/SRN NY INTO FAR NERN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 132312Z - 140015Z ISOLATED STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS CENTRAL/SRN NY INTO FAR NERN PA THROUGH 00-01Z...WITH ACTIVITY DECREASING AFTER SUNSET WITH THE ONSET OF BOUNDARY LAYER STABILIZATION. EXIT REGION OF WNWLY 60 KT MID-LEVEL JET MAX OVER LAKE HURON/LAKE ERIE COMBINED WITH COLD 500 MB TEMPERATURES /-22 TO -24 C/ WILL MAINTAIN THUNDERSTORM POTENTIAL THROUGH THE EARLY EVENING. 30-35 KT OF EFFECTIVE SHEAR AND STEEP LAPSE RATES WILL SUPPORT HAIL AS THE PRIMARY THREAT...BUT WEAK INSTABILITY WILL CONTINUE TO LIMIT SEVERE COVERAGE. ..PETERS.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ALY...BGM...BUF...CTP... 43207809 43227659 43487602 43417553 43057527 42527442 41747524 41767676 42557814 WWWW From Mcd at goshenarc.org Fri Apr 14 01:00:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 21:00:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140058 SWOMCD SPC MCD 140058 ILZ000-WIZ000-IAZ000-MNZ000-140230- MESOSCALE DISCUSSION 0492 NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT THU APR 13 2006 AREAS AFFECTED...ERN IA / SWRN WI / NRN IL CONCERNING...SEVERE THUNDERSTORM WATCH 178... VALID 140058Z - 140230Z THREAT FOR LARGE HAIL AND DAMAGING WINDS CONTINUES WITHIN WW 178. FARTHER E...ANOTHER WW WILL BE ISSUED FOR MUCH OF NRN IL AND FAR SRN WI. CLUSTER OF SUPERCELLS WILL CONTINUE TO MOVE EWD AND WILL LIKELY MERGE INTO ONE LARGE MCS WITH THE MAIN THREAT BEING DAMAGING WINDS AS IT SHIFTS EWD INTO IL AND SRN WI. THREAT OF BRIEF TORNADOES WITH INDIVIDUAL SUPERCELLS EXISTS...HOWEVER PARTICULARLY DAMAGING WINDS WITH STRONG MESOCYCLONES APPEARS MORE LIKELY AND RELATIVELY LOW BOUNDARY LAYER RH SUGGEST ANY TORNADOES WOULD BE BRIEF. THIS THREAT...HOWEVER...WILL DECREASE WITH TIME AS STORMS MERGE. ALTHOUGH INSTABILITY DIRECTLY AHEAD OF MCS IS WEAK AS SEEN ON 00Z ILX SOUNDING...SWLY LOW LEVEL JET WILL CONTINUE TO FUEL SYSTEM FROM THE SW. GIVEN LARGE TEMPERATURE/DEWPOINT SPREADS IN THE BOUNDARY LAYER DOWNSTREAM...ENHANCED DOWNDRAFT WINDS COULD RESULT. THEREFORE...A NEW WW WILL BE NEEDED E OF CURRENT WATCH. FARTHER N INTO WRN WI AND SERN MN...ENOUGH SHEAR AND INSTABILITY REMAIN FOR SVR TSTORMS WITH ADDITIONAL ACTIVITY NOW DEVELOPING ACROSS FAR WRN WI ALONG WARM FRONT. THIS WILL LIKELY POSE A WIND AND HAIL THREAT BUT TO A LESSER DEGREE COMPARED TO ACTIVITY TO THE SOUTH WHERE INSTABILITY POOL IS LARGER. ..JEWELL.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...LOT...ILX...MKX...DVN...ARX...MPX...DMX... 40438757 41099387 44269319 44739194 44879131 43788782 43088794 WWWW From Mcd at goshenarc.org Fri Apr 14 01:09:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 21:09:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140107 SWOMCD SPC MCD 140106 WIZ000-MNZ000-140230- MESOSCALE DISCUSSION 0493 NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT THU APR 13 2006 AREAS AFFECTED...WEST CENTRAL INTO CENTRAL WI CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 140106Z - 140230Z THUNDERSTORMS...WITH AN ATTENDANT SEVERE POTENTIAL...EXPECTED TO INCREASE IN AREAL COVERAGE BY MID EVENING /AROUND 03Z/ ACROSS WEST CENTRAL WI THEN SPREAD ESEWD. WW MAY BE REQUIRED NORTH OF WW 178 FOR PARTS OF CENTRAL WI. LATEST LIGHTNING DATA/SATELLITE IMAGERY SUGGESTS CONVECTIVE ACTIVITY CURRENTLY SPREADING EWD ACROSS ERN ND/NERN SD IS ASSOCIATED WITH LEADING EDGE OF DEEPER LARGE SCALE ASCENT WITH SRN CANADA/ND SHORT WAVE TROUGH. WEAK INSTABILITY OVER ERN ND SHOULD LIMIT THE SEVERE THREAT WITH PRESENT ACTIVITY OVER THAT REGION. AT 00Z...A WARM FRONT EXTENDED FROM EAST CENTRAL MN SEWD ACROSS NRN IL/NRN IND. STRENGTHENING SSWLY LLJ ACROSS ERN IA/IL INTO CENTRAL WI WILL PROVIDE A FEED OF GREATER MOISTURE/INSTABILITY TO MAINTAIN STORMS ONCE THEY DEVELOP ALONG/N OF WARM FRONT INTO CENTRAL WI. THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE OVER WEST CENTRAL WI /POTENTIALLY ERN MN/ BY 03Z AS THE ASCENT NOW LOCATED OVER ERN ND/SD ENCOUNTERS THE GREATER INSTABILITY FARTHER EAST. HAIL SHOULD BE THE PRIMARY THREAT AS MUCH OF THIS EXPECTED NEW DEVELOPMENT WILL LIKELY BE ELEVATED. ..PETERS.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...DLH...ARX...MPX... 44549253 44909294 45839293 45839129 45508972 45088889 44288914 44299023 44629096 44639195 WWWW From Mcd at goshenarc.org Fri Apr 14 03:33:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 23:33:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140331 SWOMCD SPC MCD 140331 OHZ000-MIZ000-INZ000-WIZ000-ILZ000-IAZ000-140430- MESOSCALE DISCUSSION 0494 NWS STORM PREDICTION CENTER NORMAN OK 1031 PM CDT THU APR 13 2006 AREAS AFFECTED...FAR ERN IA/CENTRAL-SRN WI/NRN IL/FAR NWRN IND CONCERNING...SEVERE THUNDERSTORM WATCH 178...179... VALID 140331Z - 140430Z SEVERE STORMS EXPECTED TO CONTINUE ACROSS MAINLY SERN PART OF WW 178 AND MUCH OF WW 179. NEW WW MAY BE NEEDED FOR SWRN LOWER MI AND CENTRAL/NRN IND BY 04Z. HP SUPERCELL CURRENTLY LOCATED OVER THE IL COUNTIES OF ROCK ISLAND...MERCER AND HENRY SHOULD CONTINUE TO MOVE SEWD ALONG MOISTURE/INSTABILITY AXIS WHICH EXTENDED SEWD INTO CENTRAL TO SERN IL. MEANWHILE...STRONGEST LEFT MOVING STORMS OVER NRN IL/SRN WI HAVE MOVED N OF WARM FRONT SUGGESTING THREAT WITH THIS ACTIVITY SHOULD BE HAIL AS THEY CONTINUE TO TRACK ENE AT 50-55 KT. 50 KT SSWLY LLJ EXTENDING FROM ERN MO INTO NRN IL/SRN WI WILL CONTINUE TO PROVIDE INFLUX OF MODERATE INSTABILITY INTO ONGOING MCS ACROSS FAR ERN IA/NRN IL/SRN WI. LLJ IS EXPECTED TO VEER TO SWLY AND TRANSLATE EWD EXTENDING INTO SRN LOWER MI OVERNIGHT. THIS WILL AID DESTABILIZATION FOR MCS TO CONTINUE TO SPREAD EWD WITH ATTENDANT THREAT FOR SEVERE STORMS. ..PETERS.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...APX...IWX...GRR...IND...GRB...LOT...ILX...MKX...DVN...ARX... 44348669 43538471 41598477 39748486 39768887 40249019 40739065 41059115 41439137 42569140 43339124 44359065 45048999 45128960 44748719 WWWW From Mcd at goshenarc.org Sat Apr 15 00:53:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 20:53:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150051 SWOMCD SPC MCD 150051 INZ000-ILZ000-150215- MESOSCALE DISCUSSION 0504 NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT FRI APR 14 2006 AREAS AFFECTED...NORTHEAST/EAST CENTRAL IL INTO CENTRAL INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 150051Z - 150215Z TORNADO WATCHES 185/187 CONTINUE UNTIL 05Z. PRIMARY TORNADO THREAT /INCLUDING THE POTENTIAL FOR A FEW STRONG TORNADOES/ CONTINUES FROM NORTHEAST IL/FAR EAST CENTRAL IL INTO CENTRAL INDIANA. A POTENTIALLY DANGEROUS SITUATION MAY DEVELOP INTO THE INDIANAPOLIS METRO AREA BY 02Z/10 PM LOCAL TIME. SCATTERED SUPERCELLS /WITH HISTORY OF TORNADOES/ CONTINUE FROM NORTHEAST IL INTO CENTRAL INDIANA AT THIS TIME. PRIMARY TORNADO POTENTIAL...INCLUDING THE POSSIBILITY FOR A STRONG TORNADO OR TWO...OVER THE NEXT SEVERAL HOURS WILL REMAIN IN AREAS ALONG/JUST NORTH OF QUASI-STATIONARY OUTFLOW BOUNDARY/EFFECTIVE BAROCLINIC ZONE THAT IS ROUGHLY ORIENTED NW-SE FROM NEAR KANKAKEE IL INTO CENTRAL INDIANA NEAR LAFAYETTE AND THE INDIANAPOLIS METRO AREA. AIDED BY A SUB-SYNOPTIC SURFACE LOW...THIS CORRIDOR IS CHARACTERIZED BY A RATHER UNSTABLE AIRMASS /00Z LINCOLN IL RAOB/...BACKED LOW LEVEL FLOW/ENLARGED LOW LEVEL HODOGRAPHS...AND A MOIST ENVIRONMENT FAVORABLE FOR A STRONG TORNADO OR TWO OVER THE NEXT COUPLE OF HOURS. INTENSE SUPERCELL IN MONTGOMERY/TIPPECANOE COUNTIES INDIANA MAY APPROACH THE INDIANAPOLIS METRO AREA BY AROUND 02Z. VERY LARGE HAIL/DAMAGING WINDS REMAINS POSSIBLE AS WELL WITH THESE ONGOING SUPERCELLS. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX...DVN... 40339030 41138935 41668811 41008656 40348503 39158544 39138691 39588959 39849025 WWWW From Mcd at goshenarc.org Sat Apr 15 01:14:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 21:14:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150112 SWOMCD SPC MCD 150112 VAZ000-PAZ000-MDZ000-WVZ000-OHZ000-KYZ000-150245- MESOSCALE DISCUSSION 0505 NWS STORM PREDICTION CENTER NORMAN OK 0812 PM CDT FRI APR 14 2006 AREAS AFFECTED...ERN-SERN OH/SW-SOUTH CENTRAL PA/WV/WRN-NRN VA/WRN MD CONCERNING...SEVERE THUNDERSTORM WATCH 186... VALID 150112Z - 150245Z ...EAST OF WW 186... AREA OF STRONG-SEVERE STORMS EXTENDING FROM FAR SWRN PA THROUGH ERN WV WILL CONTINUE TO MOVE EWD NEXT FEW HOURS...BUT OVERALL SEVERE THREAT EXPECTED TO DECREASE AS THIS ACTIVITY CONTINUES TO MOVE INTO THE HIGHER TERRAIN. STABILIZATION PROCESS IS EXPECTED TO CONTINUE ALONG/E OF THE CENTRAL APPALACHIANS /EAST OF WW 186/ GIVEN THE LOSS OF DAYTIME HEATING...AS HAS BEEN INDICATED ACROSS PARTS OF CENTRAL VA DURING THE LAST HOUR /SINCE 2330Z/. GIVEN THIS TREND AND LIMITED TIME/SPACE OF SEVERE THREAT EAST OF WW 186...A NEW WW IS NOT WARRANTED. STEEP LOW-MID LEVEL LAPSE RATES PER RNK/IAD 00Z SOUNDINGS SUGGEST ISOLATED STRONG WIND GUSTS/HAIL WILL BE POSSIBLE WITH THE STRONGER CORES THROUGH 02-03Z. ...PART OF SOUTH CENTRAL OH/WRN WV... AIR MASS ACROSS THIS PART OF WW 186 IS EXPECTED TO REMAIN MODERATELY UNSTABLE SUPPORTING A CONTINUED THREAT FOR SEVERE STORMS. UPSTREAM STORMS...CURRENTLY LOCATED ACROSS SWRN OH/SERN IND...SHOULD TRACK ESE INTO SWRN PART OF WW 186 BY 02-03Z. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...JKL...ILN... 39538266 39088087 40287902 39887777 38797761 37617895 36918031 37188152 38038268 38828278 WWWW From Mcd at goshenarc.org Sat Apr 15 03:40:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 23:40:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150339 SWOMCD SPC MCD 150338 OHZ000-KYZ000-INZ000-150515- MESOSCALE DISCUSSION 0506 NWS STORM PREDICTION CENTER NORMAN OK 1038 PM CDT FRI APR 14 2006 AREAS AFFECTED...PARTS OF CENTRAL-SERN IND/SWRN OH/NRN KY CONCERNING...TORNADO WATCH 187...188... VALID 150338Z - 150515Z SEVERE THREAT EXPECTED TO CONTINUE ACROSS CENTRAL/SERN IND INTO PARTS OF CINCINNATI METRO AREA THROUGH 05Z. THEREAFTER... STABILIZING AIR MASS IN WAKE OF ACTIVITY ACROSS CENTRAL/SRN OH SHOULD LIMIT SEVERE THREAT FARTHER SEWD INTO SOUTH CENTRAL OH AND THE REST OF NRN KY. LATE EVENING SURFACE MESO-ANALYSIS INDICATED AN OUTFLOW BOUNDARY EXTENDED FROM WEST CENTRAL IND /WARREN AND FOUNTAIN COUNTIES/ SEWD ACROSS FAR NRN KY /JUST S OF CVG/ AND THEN ESEWD INTO NERN KY TO CENTRAL WV. SEVERAL ROUNDS OF THUNDERSTORMS ACROSS MUCH OF SWRN OH HAVE CONVECTIVELY OVERTURNED/STABILIZED THE AIR MASS ALONG/N OF THIS OUTFLOW BOUNDARY. 50 KT WSWLY LLJ LOCATED ACROSS THE LOWER OH VALLEY SHOULD AID IN MAINTAINING DESTABILIZATION/SHEAR TO SUPPORT ONGOING CENTRAL/SERN IND STORM CLUSTERS AS THIS ACTIVITY REACHES THE CINCINNATI METRO AREA BETWEEN 04-05Z. DAMAGING WINDS/LARGE HAIL SHOULD BE THE PRIMARY THREATS WITH THIS ACTIVITY WITH AN ISOLATED TORNADO STILL POSSIBLE WITH ANY STORMS INTERACTING WITH THE OUTFLOW BOUNDARY WHERE LOW-LEVEL SHEAR SHOULD REMAIN ENHANCED. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...JKL...ILN...LMK...IWX...IND... 38938684 39818675 40478590 40388455 39758276 38298321 38358481 38748564 38678674 WWWW From Mcd at goshenarc.org Sat Apr 15 04:07:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 00:07:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150405 SWOMCD SPC MCD 150405 VAZ000-WVZ000-OHZ000-KYZ000-150500- MESOSCALE DISCUSSION 0507 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 14 2006 AREAS AFFECTED...PART OF SOUTH CENTRAL OH AND CENTRAL/SRN WV CONCERNING...SEVERE THUNDERSTORM WATCH 186... VALID 150405Z - 150500Z WW 186 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. MOST OF THE AIR MASS ACROSS VALID PART OF WW 186 FROM SOUTH CENTRAL OH INTO CENTRAL/SRN WV HAS BEEN CONVECTIVELY OVERTURNED BY EARLIER AND ONGOING THUNDERSTORMS...WITH ANY ASSOCIATED SEVERE THREAT HAVING DECREASED CONSIDERABLY DURING THE LAST HOUR. STRONGEST STORMS AT THIS TIME ARE LOCATED WELL UPSTREAM AROUND THE CINCINNATI OH AREA... WITH THIS ACTIVITY LIKELY WEAKENING PRIOR TO REACHING WW 186. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX...JKL...ILN... 39238259 39088171 38427965 38018007 37898074 37208143 37178166 37608227 38518280 WWWW From Mcd at goshenarc.org Sat Apr 15 04:19:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 00:19:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150417 SWOMCD SPC MCD 150417 INZ000-150445- MESOSCALE DISCUSSION 0508 NWS STORM PREDICTION CENTER NORMAN OK 1117 PM CDT FRI APR 14 2006 AREAS AFFECTED...PARTS OF CENTRAL/SERN IND CONCERNING...TORNADO WATCH 187... VALID 150417Z - 150445Z WW 187 WILL BE ALLOWED TO EXPIRE AT 05Z. STRONGEST STORMS WITHIN VALID PART OF WW 187 WERE LOCATED OVER RUSH/ DECATUR COUNTIES AND MOVING SEWD AT 40 KT. OVERALL DECREASING TREND IN SEVERE THREAT EXPECTED TO CONTINUE AS THIS ONGOING ACTIVITY MOVES INTO MAINLY THE SRN HALF OF WW 188 BY 0430-05Z. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IWX...IND... 38918683 39818642 40468560 40448493 39298540 38888559 38768604 38678665 WWWW From Mcd at goshenarc.org Sat Apr 15 06:36:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 02:36:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150634 SWOMCD SPC MCD 150634 VAZ000-150830- MESOSCALE DISCUSSION 0509 NWS STORM PREDICTION CENTER NORMAN OK 0134 AM CDT SAT APR 15 2006 AREAS AFFECTED...SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 150634Z - 150830Z THUNDERSTORMS MAY POSE A THREAT FOR ISOLATED HAIL AND STRONG WIND GUSTS AS THEY MOVE THROUGH SWRN VA NEXT FEW HOURS. TRENDS WILL CONTINUE TO BE MONITORED FOR INTENSIFICATION. EARLY THIS MORNING A SMALL CLUSTER OF STORMS CONTINUES OVER SWRN VA NEAR TIMBERLAKE. ACTIVITY IS DEVELOPING ALONG THE LEADING EDGE OF AN OUTFLOW BOUNDARY THAT CONTINUES TO SPREAD ESEWD. OBJECTIVE ANALYSIS SHOWS THE DOWNSTREAM ATMOSPHERE IS MODERATELY UNSTABLE WITH MUCAPE FROM 1500 TO 2000 J/KG AND A MODEST CAP. RECENT SURFACE OBSERVATIONS SHOW WIND GUSTS AROUND 31 KT ALONG THE GUST FRONT. GUST FRONT CONVERGENCE AND THE MODEST CAP SUGGEST STORMS MAY CONTINUE TO DEVELOP EWD NEXT FEW HOURS. THE BOUNDARY LAYER HAS UNDERGONE SOME STABILIZATION AND COOLING...AND THIS MAY SERVE AS AN OVERALL LIMITING FACTOR. HOWEVER...STEEP MID LEVEL LAPSE RATES AND MODERATE MUCAPE SUGGEST THE STRONGER STORMS MAY BE CAPABLE OF PRODUCING HAIL. INCREASING LOW-MID LEVEL WLY KINEMATIC PROFILES ASSOCIATED WITH A SHORTWAVE TROUGH MOVING ESEWD TOWARD THE MID ATLANTIC MAY ALSO ENHANCE POTENTIAL FOR ISOLATED STRONG WIND GUSTS. ..DIAL.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 37947906 37517802 36927827 36757915 37638006 WWWW From Mcd at goshenarc.org Sat Apr 15 17:01:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 13:01:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151700 SWOMCD SPC MCD 151659 NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-151800- MESOSCALE DISCUSSION 0510 NWS STORM PREDICTION CENTER NORMAN OK 1159 AM CDT SAT APR 15 2006 AREAS AFFECTED...SERN PA...SRN NJ...DELMARVA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151659Z - 151800Z POTENTIAL FOR SEVERE THUNDERSTORMS EXPECTED TO INCREASE ACROSS PORTIONS OF SERN PA...SRN NJ...AND THE DELMARVA REGION INTO THE AFTERNOON. A SEVERE THUNDERSTORM WATCH MAY BE NEEDED IN THE NEXT HOUR OR SO. ISOLATED CONVECTION APPEARS TO BE DEVELOPING NEAR COLD FRONT/LEE-TROUGH INTERSECTION NOW OVER SERN PA. AIR MASS AHEAD OF THIS DEVELOPMENT WAS BECOMING INCREASINGLY UNSTABLE WITH LATEST DIAGNOSTIC DATA INDICATING MLCAPE AROUND 1000 J/KG FROM ERN/NRN VA TO SRN NJ. ANOTHER HOUR OR SO OF HEATING SHOULD EFFECTIVELY ELIMINATE REMAINING INHIBITION AND CONTRIBUTE TO INCREASING STORM INITIATION ACROSS THE REGION. EFFECTIVE SHEAR WILL SUPPORT STORM ORGANIZATION AND INTENSIFICATION AND A FEW SUPERCELLS WITH HAIL APPEAR POSSIBLE. IN ADDITION...STORMS FORMING AND MERGING AHEAD OF THE FRONT AND LEE-TROUGH COULD EVOLVE INTO FAST MOVING SMALL SCALE LINE SEGMENTS WITH SCATTERED WIND DAMAGE POSSIBLE FROM THIS ACTIVITY. A SEVERE THUNDERSTORM WATCH MAY BE NEEDED IN THE NEXT HOUR OR SO TO COVER PARTS OF THE AREA THROUGH EARLY EVENING. ..CARBIN.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...CTP...LWX...RNK... 40287565 40257461 39707424 37877536 36947597 36727688 36927768 37327878 37907901 39337731 39887678 WWWW From Mcd at goshenarc.org Sat Apr 15 18:17:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 14:17:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151815 SWOMCD SPC MCD 151814 SDZ000-151945- MESOSCALE DISCUSSION 0511 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT SAT APR 15 2006 AREAS AFFECTED...SOUTHERN SD CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151814Z - 151945Z THREAT FOR ISOLATED LARGE HAIL MAY INCREASE THROUGH EARLY/MID AFTERNOON ACROSS SOUTHERN SD. GIVEN EXPECTED MARGINAL/ISOLATED NATURE...A SEVERE WATCH IS NOT CURRENTLY ANTICIPATED...BUT CONVECTIVE TRENDS WILL BE MONITORED. ARC OF TSTMS HAS RECENTLY INCREASED IN INTENSITY ACROSS SOUTHERN SD...LIKELY TIED TO INCREASING ELEVATED INSTABILITY VIA DRYSLOT/FORCING FOR ASCENT ASSOCIATED WITH CENTRAL HIGH PLAINS CYCLONE. 17Z RUC/09Z NAMKF SOUNDINGS SUGGEST MUCAPE WILL GENERALLY REMAIN AT 300-500 J/KG OR LESS ACROSS MUCH OF SOUTHERN SD. GIVEN THE ELEVATED NATURE OF BUOYANCY...LARGE HAIL WOULD BE THE PRIMARY HAZARD. CURRENT EXPECTATIONS ARE THAT THE THREAT WILL REMAIN SUFFICIENTLY MARGINAL/ISOLATED GIVEN MODEST INSTABILITY/CLOUD BEARING SHEARING SUCH THAT A WATCH MAY NOT BE NEEDED...HOWEVER WILL CONTINUE TO MONITOR. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FSD...ABR...UNR... 43230242 44080258 44760155 44709833 43429766 43169945 43150077 WWWW From Mcd at goshenarc.org Sat Apr 15 18:45:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 14:45:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151843 SWOMCD SPC MCD 151842 NJZ000-DEZ000-MDZ000-PAZ000-VAZ000-DCZ000-WVZ000-OHZ000-151945- MESOSCALE DISCUSSION 0512 NWS STORM PREDICTION CENTER NORMAN OK 0142 PM CDT SAT APR 15 2006 AREAS AFFECTED...UPPER OH VALLEY EAST TO SRN NJ/DELMARVA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151842Z - 151945Z AREAS ALONG AND SOUTH OF SLOW MOVING COLD FRONT...FROM SERN OH... ACROSS WV...TO DELMARVA AND SRN NJ...ARE STILL BEING MONITORED FOR A POSSIBLE SEVERE THUNDERSTORM WATCH THIS AFTERNOON. HOWEVER...RECENT TRENDS IN RADAR IMAGERY SUGGEST STORM DEVELOPMENT IS OCCURRING SLOWER THAN EARLIER EXPECTED. WAVE CLOUDS OVER AND DOWNWIND FROM THE APPALACHIAN CREST APPEAR TO BE SLOWLY ERODING AS DEEPER MIXING/HEATING CONTINUES ACROSS THE REGION AHEAD OF A SLOW MOVING FRONT. BOUNDARY LAYER WAS MOST UNSTABLE ACROSS NRN/ERN VA INTO MD ATTM AND STORMS MAY INCREASE OVER THIS AREA WHERE LEE-TROUGH/FRONT CONVERGENCE IS MAXIMIZED OVER THE NEXT 1-2 HOURS. FARTHER WEST...LIFT ALONG THE FRONTAL ZONE SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED STORMS IN MODERATELY UNSTABLE ENVIRONMENT. STRONG NWLY FLOW ALOFT WILL PERSIST ACROSS THE REGION AND RESULT IN DEEP LAYER SHEAR SUPPORTIVE OF STORM ORGANIZATION. PRIMARY LIMITING FACTOR APPEARS TO BE LACK OF GREATER LARGE SCALE FORCING FOR ASCENT AND THIS COULD LIMIT OVERALL STORM COVERAGE. IF AN AREA OF GREATER SEVERE STORM POTENTIAL BECOMES CLEARER IN THE NEXT HOUR OR SO...A WATCH IS STILL POSSIBLE FOR DEVELOPING/EVOLVING CONVECTION. ..CARBIN.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...CTP...LWX...RNK...PBZ...RLX...ILN... 38338039 38558253 39108304 39348192 39767974 39697725 39837517 39757439 38777481 38237539 38137602 38047797 WWWW From Mcd at goshenarc.org Sat Apr 15 19:10:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 15:10:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151909 SWOMCD SPC MCD 151908 NEZ000-KSZ000-152115- MESOSCALE DISCUSSION 0513 NWS STORM PREDICTION CENTER NORMAN OK 0208 PM CDT SAT APR 15 2006 AREAS AFFECTED...WEST CENTRAL/CENTRAL INTO EXTREME NORTH CENTRAL KS/EASTERN NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151908Z - 152115Z SEVERE THREAT IS LIKELY TO INCREASE ACROSS MUCH OF WEST CENTRAL/CENTRAL NEB INTO EXTREME NORTH CENTRAL KS/EASTERN NEB THROUGH MID AFTERNOON. A WATCH APPEARS LIKELY BY 20-21Z. CU FIELD CONTINUES TO EVOLVE ACROSS SOUTHWEST INTO CENTRAL NEB WITHIN WELL MIXED BOUNDARY LAYER...AHEAD OF SURFACE LOW NEAR NORTH PLATTE NEB AND IN VICINITY OF QUASI-STATIONARY FRONT/DRYLINE TRIPLE POINT. GIVEN AMPLE INSOLATION/WEAKENING SURFACE BASED INHIBITION AND INCREASINGLY STRONG FORCING FOR ASCENT ACROSS WEST CENTRAL/CENTRAL NEB...INITIATION OF DEEP CONVECTION APPEARS LIKELY IN THE NEXT FEW HOURS. PRIMARY HAZARDS WILL LIKELY BE LARGE HAIL AND DAMAGING WIND GUSTS...ATTRIBUTABLE TO MODEST INSTABILITY AND WELL MIXED BOUNDARY LAYER. SOME THREAT FOR TORNADOES MAY EXIST GIVEN AMBIENT VERTICAL VORTICITY/STEEP LAPSE RATE ENVIRONMENT IN OTHERWISE MARGINAL MOISTURE /UPPER 40S TO MIDDLE 50S SURFACE DEWPOINTS/. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...GID...LBF... 41050041 41210144 42610157 42709844 42229754 40239689 39999795 40819917 WWWW From Mcd at goshenarc.org Sat Apr 15 20:50:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 16:50:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152048 SWOMCD SPC MCD 152048 MOZ000-OKZ000-KSZ000-152215- MESOSCALE DISCUSSION 0514 NWS STORM PREDICTION CENTER NORMAN OK 0348 PM CDT SAT APR 15 2006 AREAS AFFECTED...EASTERN KS/NORTHEAST OK INTO WESTERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152048Z - 152215Z MONITORING CONVECTIVE TRENDS FOR SURFACE BASED STORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS EAST CENTRAL KS INTO OK. A WATCH COULD BE NEEDED IN THE NEXT FEW HOURS...NAMELY ACROSS EASTERN KS INTO WESTERN MO. MID LEVEL CONVECTION ABOVE WELL CAPPED BOUNDARY LAYER -- REFERENCE SPECIAL 18Z RAOBS FROM TOPEKA KS/SPRINGFIELD MO -- HAS PERSISTED MUCH OF THE AFTERNOON ACROSS EASTERN KS...WITH RELATIVELY NEWER MID LEVEL DEVELOPMENT ACROSS NORTHEAST KS IN AREAS NORTH/WEST OF TULSA. WHILE THIS ACTIVITY COULD POSE A HAIL THREAT AS IT PROGRESSES ENE INTO MO...PRIMARY SEVERE THREAT/SURFACE BASED DEVELOPMENT MAY DEVELOP IN VICINITY OF DRYLINE ACROSS EAST CENTRAL KS...CURRENTLY FROM NEAR CONCORDIA-SALINA TO WICHITA...AND PERHAPS EVEN INTO NORTH CENTRAL/NORTHEAST OK. BOUNDARY LAYER CU HAS EVOLVED OVER THE PAST HALF HOUR INVOF THE DRYLINE. WHILE LIKLIHOOD/EXTENT OF SURFACE BASED CONVECTION REMAINS UNCLEAR...STRONG HEATING COUPLED WITH FORCING FOR ASCENT ASSOCIATED WITH CENTRAL HIGH PLAINS CYCLONE MAY LEAD TO INITIATION OF DEEP CONVECTION LATE THIS AFTERNOON/EARLY EVENING. COMBINATION OF MODERATE INSTABILITY/AMPLE EFFECTIVE BULK SHEAR WOULD BE FAVORABLE FOR SUPERCELLS...WITH ATTENDANT THREATS OF LARGE HAIL/DAMAGING WINDS. TORNADO THREAT MAY INCREASE AS STORMS DEVELOP EASTWARD ACROSS FAR EASTERN KS INTO WESTERN MO EARLY THIS EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN... 39169705 39529616 39829434 39379332 37409354 36579502 36419683 37369744 WWWW From Mcd at goshenarc.org Sat Apr 15 21:50:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 17:50:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152148 SWOMCD SPC MCD 152148 OKZ000-TXZ000-152315- MESOSCALE DISCUSSION 0515 NWS STORM PREDICTION CENTER NORMAN OK 0448 PM CDT SAT APR 15 2006 AREAS AFFECTED...CENTRAL OK/FAR NORTH CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152148Z - 152315Z MONITORING FOR HIGHLY CONDITIONAL/ISOLATED SEVERE THREAT ACROSS CENTRAL OK INTO FAR NORTH CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. A WATCH IS NOT ANTICIPATED. MONITORING EVOLUTION OF POCKETS OF HIGH BASED BOUNDARY LAYER CU IN VICINITY OF DRYLINE ACROSS CENTRAL OK INTO NORTH CENTRAL TX. LATEST ANALYSIS/OBSERVATIONAL TRENDS FEATURES STRONG MIXING/WEAKENING SURFACE BASED CINH -- WITH TEMPERATURES OVER 100F IN SOUTHWEST OK -- AND AMPLE MASS CONVERGENCE INVOF DRYLINE FROM WEST OF THE OKC METRO AREA TO NEAR DUNCAN OK AND EAST OF WICHITA FALLS TX. IN THIS CORRIDOR...VIA DEEP MIXING/GLANCING UPPER SUPPORT...SOME POTENTIAL EXISTS FOR A STORM OR TWO TO DEVELOP LATE THIS AFTERNOON/EARLY EVENING ACROSS CENTRAL OK/NORTH CENTRAL TX. CONDITIONAL POTENTIAL WOULD EXIST FOR LARGE HAIL AND STRONG WIND GUSTS THROUGH EARLY EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...FWD...OUN... 35909754 36239665 35749615 34009656 33429750 33949844 WWWW From Mcd at goshenarc.org Sat Apr 15 22:02:56 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 18:02:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152201 SWOMCD SPC MCD 152200 IAZ000-MOZ000-KSZ000-NEZ000-SDZ000-152330- MESOSCALE DISCUSSION 0516 NWS STORM PREDICTION CENTER NORMAN OK 0500 PM CDT SAT APR 15 2006 AREAS AFFECTED...CENTRAL/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO CONCERNING...TORNADO WATCH 190... VALID 152200Z - 152330Z TORNADO WATCH 190 CONTINUES UNTIL 03Z ACROSS CENTRAL/EASTERN NEB AND NORTHEAST KS. AN ADDITIONAL TORNADO WATCH WILL BE ISSUED SOON FOR WESTERN IA AND NORTHWEST MO. AMBIENT ENVIRONMENT REMAINS FAVORABLE FOR SUPERCELLS AND LARGE HAIL/ISOLATED TORNADOES ACROSS MUCH OF CENTRAL/EASTERN NEB AND NORTHEAST KS...FOCUSED INVOF DRYLINE AND OCCLUSION/WARM FRONT TRIPLE POINT. TORNADOES HAVE ALREADY BEEN REPORTED IN GAGE COUNTY NEB. IN PRESENCE OF MODERATE INSTABILITY/AMPLE VERTICAL SHEAR...STORMS WILL CONTINUE TO DEVELOP EASTWARD EARLY THIS EVENING INTO WESTERN IA/NORTHWEST MO...WITH STORMS POTENTIALLY BREACHING THE EASTERN EXTENT OF TORNADO WATCH 190 BY AROUND 23Z. FLOW FIELDS WILL REMAIN FAVORABLE FOR ROTATING STORMS/ISOLATED TORNADOES...WITH LOW LEVEL MOISTURE CONTINUING TO INCREASE ALONG THE MISSOURI RIVER ACROSS NORTHWEST MO/SOUTHWEST IA EARLY THIS EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP...GID...LBF... 42459827 42569653 42419426 41389305 39839303 39219392 39309571 40189639 41279710 41809867 WWWW From Mcd at goshenarc.org Sat Apr 15 23:01:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:01:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152259 SWOMCD SPC MCD 152259 MDZ000-VAZ000-NCZ000-WVZ000-160030- MESOSCALE DISCUSSION 0517 NWS STORM PREDICTION CENTER NORMAN OK 0559 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS WV...VA...MD...DE...DC CONCERNING...SEVERE THUNDERSTORM WATCH 189...191... VALID 152259Z - 160030Z PRONOUNCED SUPERCELL WITH REFLECTIVITY HOOK HAS MOVED SEWD OFFSHORE CAPE CHARLES REGION AND OVER ATLANTIC. STRONGEST VERTICAL SHEAR PROFILES ARE EVIDENT FROM SRN DELMARVA PENINSULA SWD ALONG COASTAL FRONT INTO EXTREME NERN NC...W OF WHICH SFC FLOW IS WLY. SFC MESOANALYSIS SHOWS COLD FRONT AND ATTENDANT SFC DRYING/VEERING FROM SERN PA SWWD ACROSS SRN WV. AIR MASS IN BETWEEN THESE BOUNDARIES REMAINS CHARACTERIZED BY STRONG HEATING AND SFC DEW POINTS GENERALLY IN 50S F...EXCEPT ACROSS SRN WV WHERE MIXING HAS YIELDED 40S F VALUES. LACK OF SUBSTANTIAL CONVERGENCE IN THIS AIR MASS WILL CONTINUE TO LIMIT CONVECTIVE COVERAGE...THOUGH ANY SUSTAINED TSTMS SUCH AS THOSE MOVING SEWD ACROSS NORTHUMBERLAND COUNTY VA MAY PRODUCE DAMAGING WIND AND LARGE HAIL FROM THERE ACROSS SRN CHESAPEAKE BAY TO PORTIONS SRN ACCOMACK/NORTHAMPTON COUNTIES. VIS IMAGERY AND REFLECTIVITY TRENDS INDICATE SEVERE TSTM POTENTIAL HAS DIMINISHED SUBSTANTIALLY ACROSS WV...EWD ACROSS PORTIONS WRN/CENTRAL/NRN VA...EWD TO CENTRAL/NRN DELMARVA REGION. OVERALL CONVECTIVE COVERAGE AND INTENSITY SHOULD CONTINUE TO DIMINISH DURING NEXT FEW HOURS WITH LOSS OF DIURNAL HEATING AND INCREASING SBCINH. ..EDWARDS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 38097978 38357952 38467927 38587744 38477584 38347518 38177480 37727504 37097542 36557552 36487599 36577867 37727859 WWWW From Mcd at goshenarc.org Sat Apr 15 23:19:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:19:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152317 SWOMCD SPC MCD 152317 IAZ000-MOZ000-KSZ000-NEZ000-SDZ000-160045- MESOSCALE DISCUSSION 0518 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CDT SAT APR 15 2006 AREAS AFFECTED...NORTHERN/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO CONCERNING...TORNADO WATCH 190...192... VALID 152317Z - 160045Z VALID PORTION OF TORNADO WATCH 190 CONTINUES UNTIL 03Z...TORNADO WATCH 192 CONTINUES UNTIL 05Z. ISOLATED TORNADO AND LARGE HAIL/DAMAGING WIND THREAT CONTINUES ACROSS VALID PORTIONS OF TORNADO WATCHES 190/192 THIS EVENING FROM NORTHERN/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO. POTENTIALLY SIGNIFICANT TORNADO DAMAGE WAS REPORTED EARLIER NEAR BEATRICE NEB. WITHIN THESE TORNADO WATCHES...RELATIVELY GREATEST TORNADO POTENTIAL THROUGH EARLY EVENING APPEARS TO BE FROM EXTREME SOUTHEAST NEB/FAR NORTHEAST KS INTO SOUTHWEST IA AND NORTHWEST MO...INCLUDING AREAS FROM TOPEKA KS-ST JOSEPH MO-MARYVILLE MO TO RED OAK/CRESTON IA. IN THIS CORRIDOR...SCATTERED SUPERCELLS ARE ONGOING AND LIKELY TO PERSIST IN RATHER FAVORABLE ENVIRONMENT INVOF DRYLINE AND WARM FRONT/OCCLUSION. THE NEAR STORM ENVIRONMENT IS CHARACTERIZED BY BACKED SOUTHEASTERLY WINDS AND BOUNDARY LAYER DEWPOINTS IN THE LOWER 60S/SURFACE TEMP-DEWPOINT DEPRESSIONS OF 15-20 F. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP...LBF... 42689901 42569653 42119481 41249313 39839303 39219392 38529576 39989591 41399685 42049893 WWWW From Mcd at goshenarc.org Sat Apr 15 23:43:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:43:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152341 SWOMCD SPC MCD 152341 IAZ000-MNZ000-NEZ000-SDZ000-160115- MESOSCALE DISCUSSION 0519 NWS STORM PREDICTION CENTER NORMAN OK 0641 PM CDT SAT APR 15 2006 AREAS AFFECTED...SOUTHEAST SD/NORTHWEST IA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152341Z - 160115Z SEVERE THREAT MAY DEVELOP THROUGH EARLY/MID EVENING ACROSS FAR SOUTHEAST SD INTO NORTHWEST IA. ALTHOUGH A SEVERE TSTM WATCH IS NOT CURRENTLY ANTICIPATED...WILL CONTINUE TO MONITOR CONVECTIVE TRENDS ON NORTHERN PERIPHERY OF TORNADO WATCHES 190/192. ARC OF STRONG/SEVERE TSTMS...WITH SOME EMBEDDED SUPERCELLS AND HISTORY OF LARGE HAIL...EXTENDS ACROSS FAR NORTHEAST NEB TO ALONG THE NEB/IA BORDER AS OF 2340Z. AS THIS ACTIVITY SPREADS FURTHER EAST/NORTHEAST...AT LEAST AN ISOLATED THREAT MAY EXTEND INTO FAR SOUTHEAST SD/NORTHWEST IA THIS EVENING. WITH WARM SECTOR/RICHER THETA-E REMAINING SUFFICIENTLY SOUTH OF THE AREA...PRIMARY SEVERE HAZARD WOULD BE LARGE HAIL. LATEST RUC FORECAST SOUNDINGS SUGGEST POTENTIAL FOR 500-1000 J/KG ELEVATED MUCAPE...MAXIMIZED THIS EVENING ACROSS NORTHWEST IA. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...FSD... 43229733 43629730 43659624 43289332 42399331 42309464 42379615 42509665 WWWW From Mcd at goshenarc.org Sun Apr 16 02:16:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 22:16:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160214 SWOMCD SPC MCD 160214 MOZ000-IAZ000-KSZ000-160345- MESOSCALE DISCUSSION 0520 NWS STORM PREDICTION CENTER NORMAN OK 0914 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS ERN KS...NWRN MO...WRN IA CONCERNING...TORNADO WATCH 192... VALID 160214Z - 160345Z BROKEN LINE OF SEVERE TSTMS FROM MKC AREA NNEWD TO SW OF DSM INCLUDED AT LEAST TWO POTENTIALLY TORNADIC SUPERCELLS AS OF 2Z -- IN N-CENTRAL/NERN PORTIONS KC METRO AND DEKALB/DAVIESS COUNTY MO. ALL MODES OF SEVERE REMAIN POSSIBLE FROM THIS BAND AS IT MOVES ENEWD ACROSS NWRN MO AND S-CENTRAL IA NEXT 2-3 HOURS. MEANWHILE SEVERE POTENTIAL IS INCREASING OVER PORTIONS E-CENTRAL KS AND W-CENTRAL MO S OF WW 192 WILL BE MONITORED FOR POSSIBLE WW. MODIFIED TOP RAOB AND RUC SOUNDINGS INDICATE EFFECTIVE LAYER PARCELS -- IN INFLOW REGION OF NWRN MO CONVECTION -- MAY BECOME INCREASINGLY ELEVATED ABOVE SFC THROUGH ABOUT 4Z...INDICATING GRADUAL DECREASE IN TORNADO AND SEVERE WIND POTENTIAL. MEANWHILE...LARGE LOW LEVEL HODOGRAPHS AND FAVORABLE DEEP-LAYER SHEAR WILL SUPPORT SUPERCELLS...WITH 0-3 KM SRH UP TO NEAR 600 J/KG AND MLCAPES 1000-1500 J/KG IN PROFILER/VWP DATA AND MODIFIED MODEL SOUNDINGS. FARTHER SW...SFC MESOANALYSIS SHOWS COLD FRONT HAS MERGED WITH DRYLINE ACROSS PORTIONS ERN KS -- FROM LWC AREA SWWD ACROSS COWLEY COUNTY. THIS PROCESS SHOULD CONTINUE/PROPAGATE SWWD ALONG DRYLINE INTO S-CENTRAL KS AND N-CENTRAL OK. CONVECTION HAS DEVELOPED ALONG COMBINED BOUNDARY FROM LWC TO GREENWOOD COUNTY KS...IN ZONE OF MAXIMIZED LOW LEVEL CONVERGENCE ASSOCIATED WITH FRONTAL/DRYLINE ASCENT. STRONG CINH IS EVIDENT ACROSS NRN OK...SO EVEN WITH FRONTAL LIFT...BACKBUILDING SHOULD BE LIMITED TO N OF KS/OK BORDER. DEEP-LAYER WIND AND SHEAR VECTORS HAVE SIGNIFICANT COMPONENT PARALLEL TO FORCING BOUNDARY...SUPPORTING CONTINUED LINEAR MODE. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...SGF...DMX...EAX...TOP...ICT... 37739608 38259548 38999491 39409419 39879392 40269383 40699392 41269415 41909489 42209441 42149350 41209257 40319232 39489228 38929285 38129401 37779547 WWWW From Mcd at goshenarc.org Sun Apr 16 03:48:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 23:48:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160346 SWOMCD SPC MCD 160346 ILZ000-IAZ000-WIZ000-MOZ000-160545- MESOSCALE DISCUSSION 0521 NWS STORM PREDICTION CENTER NORMAN OK 1046 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS E-CENTRAL/SERN IA...NERN MO...EXTREME NWRN IL. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 160346Z - 160545Z BAND OF STRONG-SEVERE TSTMS NOW OVER ERN-MOST PORTIONS WW 192 IS EXPECTED TO LIFT NEWD TO AREA BETWEEN CID-UIN THROUGH APPROXIMATELY 7Z. MAIN SEVERE POTENTIAL WILL TRANSITION TO HAIL...WITH OCCASIONAL STRONG-SEVERE GUSTS ALSO POSSIBLE PARTICULARLY OVER MO. AREA WILL BE MONITORED FOR POSSIBLE WW. VERTICAL SHEAR PROFILES ARE STRENGTHENING WITH TIME ACROSS THIS AREA AS MID/UPPER LEVEL SPEED MAX APCHS...ASSOCIATED WITH NEARLY VERTICALLY STACKED LOW OVER ERN NEB. HOWEVER...GIVEN DECELERATION OF THAT CYCLONE AND FCST MOTION OF MAIN BAND OF LOW LEVEL CONVECTIVE FORCING...PRIND ACTIVITY WILL OUTRUN EWD SPREAD OF OPTIMAL DEEP-LAYER SHEAR AS WELL. INFLOW PARCELS ARE FCST TO BECOME MORE ELEVATED OFF SFC WITH TIME AND WITH NWD EXTENT...GIVEN COMBINATION OF DIABATIC SFC COOLING AND PRECIP COOLING OVER IA. PARCELS MAY REMAIN NEARLY SFC-BASED FOR ANOTHER FEW HOURS ACROSS PORTIONS NERN MO...WHERE BOTH MUCAPE AND SEVERE POTENTIAL SHOULD BE MAXIMIZED. EFFECTIVE SHEARS 35-50 KT ARE EVIDENT IN RUC FCST SOUNDINGS BOTH FOR CONVECTION ROOTED IN 800-900 MB LAYER OVER IA...AND ANYWHERE BETWEEN SFC-850 MB ACROSS NERN MO. MUCAPES 1000-1500 J/KG ARE EXPECTED. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...ARX...DMX...EAX... 39289238 39849236 40049231 40539233 40749256 41079272 41529289 42019304 42869341 43339222 43239153 42539058 41929022 40909043 40489075 39419178 39249222 WWWW From Mcd at goshenarc.org Sun Apr 16 04:41:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 00:41:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160439 SWOMCD SPC MCD 160439 MOZ000-ILZ000-160545- MESOSCALE DISCUSSION 0522 NWS STORM PREDICTION CENTER NORMAN OK 1139 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS WRN/NRN MO AND CENTRAL/SRN IA. CONCERNING...TORNADO WATCH 192... VALID 160439Z - 160545Z CONVECTIVE COVERAGE/INTENSITY...AND ACCORDINGLY SEVERE POTENTIAL...IS DIMINISHING SIGNIFICANTLY IN WW. REMAINDER WW MAY BE CANCELED BEFORE SCHEDULED 5Z EXPIRATION OR ALLOWED TO EXPIRE AT THAT TIME. ACTIVITY STILL IN ERN-MOST COUNTIES OF WW NEAR IRK -- ALONG TAIL END OF MCS -- IS EXPECTED TO MOVE NEWD ACROSS NERN MO AND SERN IA WITH OCCASIONAL HAIL AND STRONG-SEVERE GUSTS POSSIBLE. REF SPC MESOSCALE DISCUSSION 520 FOR DETAILED DISCUSSION ON AREA E OF WW. MEANWHILE...INITIAL LINE OF FRONTALLY FORCED TSTMS OVER SERN KS MOSTLY HAS WEAKENED...EXCEPT FOR ISOLATED SEVERE TSTM LOCATED OVER VERNON COUNTY MO...AS OF 415Z. THIS TSTM HAS DISPLAYED INTERMITTENT SUPERCELL CHARACTERISTICS AND PRODUCED HAIL ESTIMATED UP TO 1.75 INCH DIAMETER...IN ENVIRONMENT OF STRONG LOW LEVEL SHEAR. 50-60 KT LLJ CONTRIBUTES TO 0-3 KM SRH EXCEEDING 700 J/KG OVER NARROW CORRIDOR AHEAD OF CONVECTIVE BAND. EFFECTIVE SHEARS BASED ON RUC SOUNDINGS HAVE WEAKENED CONSIDERABLY BASED ON STRONG SBCINH...ALTHOUGH SLGT MODIFICATIONS RESULT IN LIFTED PARCELS ROOTED NEAR/SLIGHTLY ABOVE SFC. CINH SHOULD CONTINUE TO LIMIT CONVECTIVE COVERAGE...BUT SRN/CENTRAL MO AREA WILL BE MONITORED FOR POSSIBLE WW. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...SGF...EAX... 37629456 38199386 38769341 39419286 40359221 40129083 37879094 WWWW From Mcd at goshenarc.org Sun Apr 16 12:17:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 08:17:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161215 SWOMCD SPC MCD 161215 KYZ000-INZ000-TNZ000-ILZ000-161415- MESOSCALE DISCUSSION 0523 NWS STORM PREDICTION CENTER NORMAN OK 0715 AM CDT SUN APR 16 2006 AREAS AFFECTED...EXTREME SERN IL...WRN KY AND SRN IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161215Z - 161415Z THUNDERSTORMS MOVING INTO WRN KY FROM EXTREME SERN IL MAY CONTINUE TO POSE A THREAT FOR ISOLATED MARGINALLY SEVERE HAIL NEXT COUPLE HOURS. THE THREAT DOES NOT APPEAR SUFFICIENT TO WARRANT A WW AT THIS TIME. EARLY THIS MORNING STORMS WERE DEVELOPING FROM EXTREME SRN IL INTO WRN KY AND SPREADING EWD. STORMS ARE ELEVATED AND ROOTED NEAR 700 MB BASED ON RUC SOUNDING DATA. STEEP MID LEVEL LAPSE RATES AROUND 8 C/KM AND EFFECTIVE CLOUD LAYER SHEAR SUPPORTIVE OF UPDRAFT ROTATION WILL SUPPORT HAIL WITH THE STRONGER STORMS. HOWEVER...MODEST MUCAPE AOB 800 J/KG SUGGESTS OVERALL HAIL SIZE SHOULD GENERALLY REMAIN 1 INCH OR LESS. FORCING FOR ASCENT ASSOCIATED WITH A WSWLY LOW LEVEL JET AND A VORTICITY LOBE ROTATING THROUGH BASE OF UPPER TROUGH WILL CONTINUE TO SUPPORT DEVELOPMENT OF STORMS THROUGH WRN KY AND INTO SRN IL NEXT COUPLE HOURS. ACTIVITY IS SUBSEQUENTLY EXPECTED TO BEGIN A WEAKENING TREND AS THE LOW LEVEL JET DIMINISHES LATER THIS MORNING. ..DIAL.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...IND...PAH... 36588898 37478899 38888697 38138575 36638738 WWWW From Mcd at goshenarc.org Sun Apr 16 16:00:22 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 12:00:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161558 SWOMCD SPC MCD 161557 WIZ000-ILZ000-MOZ000-IAZ000-MNZ000-161800- MESOSCALE DISCUSSION 0524 NWS STORM PREDICTION CENTER NORMAN OK 1057 AM CDT SUN APR 16 2006 AREAS AFFECTED...ERN IA....SRN WI...NWRN IL...NERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161557Z - 161800Z THREAT FOR HAIL PRODUCING THUNDERSTORMS WAS INCREASING ACROSS NERN IA...SWRN WI...AND PARTS OF NWRN IL LATE THIS MORNING. AREAS FROM SCNTRL/SERN IA...EAST/SOUTHEAST TO NERN MO/WRN IL MAY SEE AN INCREASE IN SURFACE-BASED STORMS NEXT FEW HOURS. WATCHES ARE POSSIBLE ACROSS PARTS OF THESE AREAS...PROBABLY WITHIN 1-2 HOURS. ARC OF CONVECTION WAS INCREASING IN COVERAGE AHEAD OF DEEP LAYER CYCLONE OVER IA THIS MORNING. THIS ACTIVITY WAS DEVELOPING TO THE NORTH OF THE SURFACE WARM FRONT AND EAST OF THE LOW WHERE STRONGER DYNAMIC FORCING ASSOCIATED WITH THE LARGE SCALE SYSTEM WAS BEGINNING TO OVERSPREAD LOW LEVEL WARM/MOIST CONVEYOR BELT. GIVEN LAPSE RATES EVIDENT ON MORNING SOUNDINGS FROM ILX AND DVN...EXPECT THESE STORMS TO PRODUCE SOME HAIL. WHILE THE CONVECTION CURRENTLY NORTH OF THE WARM FRONT WAS LIKELY ROOTED ABOVE CAPPED BOUNDARY LAYER...STORMS ARE EXPECTED TO ROOT INTO MOIST AND INCREASINGLY UNSTABLE AIR MASS NEAR SFC LOW...AND ESEWD FROM THE SFC LOW ALONG THE WARM FRONT...AND AHEAD OF WIND SHIFT/CONFLUENCE LINE MOVING EAST ACROSS NERN MO. DEEP LAYER VORTICITY AND LOW LEVEL CAPE DEVELOPING NEAR THE SFC LOW...AND STRONG LOW LEVEL SHEAR/HELICITY IN THE VICINITY OF THE WARM FRONT SHOULD SUPPORT ROTATING STORMS UPDRAFTS/SUPERCELLS. THIS ACTIVITY IS EXPECTED TO INTENSIFY AS GREATER WARM SECTOR DESTABILIZATION OCCURS INTO THE AFTERNOON. THE POTENTIAL FOR LARGE HAIL...AND AN INCREASING CHANCE OF DAMAGING WINDS/TORNADOES...SUGGEST WATCHES WILL BE NEEDED OVER PARTS OF THE REGION OVER THE NEXT FEW HOURS. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX...DMX...EAX... 40418903 40088919 39618979 39189043 38899092 38769157 38779239 39579231 40229269 40589308 40819363 41319379 41949377 42359353 43139284 43339243 43529131 43649024 43198864 42708843 41958854 40888894 WWWW From Mcd at goshenarc.org Sun Apr 16 18:10:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 14:10:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161808 SWOMCD SPC MCD 161808 INZ000-ILZ000-161945- MESOSCALE DISCUSSION 0525 NWS STORM PREDICTION CENTER NORMAN OK 0108 PM CDT SUN APR 16 2006 AREAS AFFECTED...EASTERN IL INTO CENTRAL/NORTHERN INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161808Z - 161945Z A TORNADO WATCH APPEARS LIKELY BY 19Z-20Z ACROSS EASTERN IL INTO CENTRAL/NORTHERN INDIANA. THIS MAY INCLUDE AN UPGRADE OF THE NORTHEAST IL/NORTHWEST INDIANA PORTION OF SEVERE TSTM WATCH 194. WATER VAPOR IMAGERY/SURFACE ANALYSIS DEPICTS VERTICALLY STACKED LOW ACROSS SOUTH CENTRAL/SOUTHEAST IA...WITH WARM FRONT EXTENDING E/SE ACROSS CENTRAL IL INTO CENTRAL INDIANA...LARGELY PARALLEL WITH THE INTERSTATE 74 CORRIDOR. MODERATELY AGGRESSIVE DESTABILIZATION CONTINUES TO OCCUR IN PRESENCE OF AMPLE INSOLATION...WITH PROGRESSIVELY ACTIVE CU FIELD...ESPECIALLY NOTED IN BOTH SOUTH CENTRAL IL AND SOUTH CENTRAL INDIANA AT THIS TIME. ACCORDINGLY...OBJECTIVE ANALYSIS/ADJUSTED RUC SOUNDINGS SUGGESTS NEGLIGIBLE SURFACE BASED CINH FROM CENTRAL IL INTO CENTRAL INDIANA...WITH POTENTIAL FOR 1500 J/KG MLCAPE IN THE AMBIENT WARM SECTOR. MOST LIKELY SCENARIO IS FOR STRONG/SEVERE STORMS TO SPREAD EASTWARD OUT OF WESTERN IL INTO EASTERN IL/WESTERN INDIANA THROUGH MID/LATE AFTERNOON...ALTHOUGH IT REMAINS A DISTINCT POSSIBILITY FOR SOMEWHAT SEPARATE DEVELOPMENT IN VICINITY OF WARM FRONT THIS AFTERNOON. EITHER WAY...THREAT FOR SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES WILL STEADILY INCREASE REMAINDER OF THE AFTERNOON. TORNADO POTENTIAL WILL BE MAXIMIZED IN CORRIDOR ALONG/NORTH OF WARM FRONT FROM EAST CENTRAL IL INTO CENTRAL/NORTH CENTRAL INDIANA...WHERE BOUNDARY LAYER FLOW WILL TEND TO REMAIN BACKED WITH SUFFICIENTLY CURVED/ENLARGED LOW LEVEL HODOGRAPHS. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX... 41328829 41288645 40498518 39348489 38808620 38998790 40078855 WWWW From Mcd at goshenarc.org Sun Apr 16 18:21:05 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 14:21:05 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161819 SWOMCD SPC MCD 161818 ILZ000-MOZ000-IAZ000-WIZ000-161915- MESOSCALE DISCUSSION 0526 NWS STORM PREDICTION CENTER NORMAN OK 0118 PM CDT SUN APR 16 2006 AREAS AFFECTED...SERN IA...NERN MO...WRN IL CONCERNING...TORNADO WATCH 193... VALID 161818Z - 161915Z SEVERE STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY INSIDE OF TORNADO WATCH 193 OVER THE NEXT HOUR. LATEST ANALYSIS PLACES OCCLUDED LOW OVER SCNTRL IA WITH WARM FRONT EXTENDING EAST INTO NRN IL AND WIND SHIFT/CONFLUENCE AXIS DEVELOPING EAST INTO WRN IL. STRONGLY DIFFLUENT MID LEVEL FLOW AHEAD OF THE DEEP LAYER CYCLONE WAS ACTING ON DESTABILIZING WARM SECTOR AIR MASS FROM SERN IA ACROSS CNTRL IL AND SUPPORTING INCREASING TSTM DEVELOPMENT OVER THESE AREAS. DEEP LAYER SHEAR OF 40-50KT ACROSS IL PORTIONS OF THE WATCH IS MORE THAN ADEQUATE FOR SUPERCELLS AND EXPECT STORMS NOW DEVELOPING ACROSS CNTRL IL TO REACH SEVERE LEVELS SHORTLY. LARGE HAIL APPEARS TO BE THE MAIN THREAT FROM THIS CONVECTION. HOWEVER...STORMS NEAR OR CROSSING THE WARM FRONT...FROM GBG TO PIA...WILL NEED TO BE MONITORED FOR LOW LEVEL ROTATION AND POSSIBLE TORNADO THREAT GIVEN EFFECTIVE HELICITY VALUES 150-200 MS/S2 BASED ON CELL WSW MOTION AT 25KT. STORMS NEAR THE LOW AND EAST TO DVN AREA WERE DEVELOPING IN A WEAKER SHEAR ENVIRONMENT DUE TO WEAKER FLOW NEAR THE LOW CENTER. THIS IS FURTHER SUPPORTED BY LATEST DVN SOUNDING. HOWEVER...DVN SOUNDING ALSO DEPICTS SUFFICIENT LOW LEVEL CAPE FOR MODEST UPDRAFT STRETCHING. GIVEN STRONG BACKGROUND VORTICITY IN VICINITY OF THE LOW...A FEW OF THESE CELLS COULD ACQUIRE ROTATION AND POSE A HAIL AND BRIEF TORNADO THREAT INTO THIS AFTERNOON. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...LOT...ILX...LSX...DVN...ARX...DMX...EAX... 42609347 42629064 40488850 38418828 38169132 40539246 40569349 42149407 42189356 WWWW From Mcd at goshenarc.org Sun Apr 16 20:13:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:13:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162011 SWOMCD SPC MCD 162010 VAZ000-WVZ000-162145- MESOSCALE DISCUSSION 0527 NWS STORM PREDICTION CENTER NORMAN OK 0310 PM CDT SUN APR 16 2006 AREAS AFFECTED...SRN WV...WRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 162010Z - 162145Z A COUPLE OF SEVERE THUNDERSTORMS APPEAR POSSIBLE ACROSS PORTIONS OF WV AND WRN VA OVER THE NEXT HOUR OR SO. ANTICIPATED SEVERE POTENTIAL IN TERMS OF AREAL COVERAGE AND DURATION DOES NOT CURRENTLY APPEAR GREAT ENOUGH TO WARRANT A WATCH IN THIS AREA. ISOLATED STORMS HAVE INITIATED NEAR STATIONARY FRONT CROSSING THE CNTRL APPALACHIANS FROM WRN VA INTO SERN WV. DEVELOPMENT OF THIS ACTIVITY WAS BEING AIDED BY APPROACH OF WEAK SHORT WAVE TROUGH...UPSLOPE COMPONENT OF THE LOW LEVEL FLOW...AND DIURNAL DESTABILIZATION. LATEST DIAGNOSTIC DATA SUGGESTS THAT SHEAR AND INSTABILITY ACROSS THE REGION SHOULD SUPPORT A COUPLE OF ORGANIZED STORMS WITH SOME CHANCE FOR HAIL AND ISOLATED DAMAGING WINDS. HOWEVER...WEAK LARGE SCALE FORCING FOR ASCENT...AND DIURNAL NATURE OF THE INSTABILITY...WOULD SUGGEST THAT SEVERE THREAT SHOULD REMAIN LIMITED IN TIME AND SPACE. THERE IS SOME INDICATION IN LATEST GUIDANCE THAT STORM COVERAGE MAY INCREASE ACROSS PARTS OF THE REGION LATER THIS EVENING AS STRONGER FORCING DEVELOPS EWD FROM THE OH VALLEY. A WATCH IS NOT BEING PLANNED AT PRESENT. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX... 37107906 37028122 37288184 37598172 37778072 37877931 37687898 WWWW From Mcd at goshenarc.org Sun Apr 16 20:26:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:26:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162024 SWOMCD SPC MCD 162024 KYZ000-INZ000-ILZ000-MOZ000-162230- MESOSCALE DISCUSSION 0528 NWS STORM PREDICTION CENTER NORMAN OK 0324 PM CDT SUN APR 16 2006 AREAS AFFECTED...SOUTHEAST MO/SOUTHERN IL/WESTERN KY/SOUTHWEST INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 162024Z - 162230Z CLOSELY MONITORING DEVELOPMENTAL TRENDS ACROSS FAR SOUTHEAST MO/SOUTHERN IL INTO WESTERN KY/SOUTHWEST INDIANA FOR POSSIBILITY OF A WATCH ISSUANCE. ON SOUTHERN PERIPHERY OF TORNADO WATCH 193...MODERATE CU FIELD EXISTS INVOF SURFACE TROUGH ACROSS FAR SOUTHEAST MO/FAR SOUTHWEST IL...NAMELY FROM THE ST LOUIS METRO TO NEAR FARMINGTON MO AND POPLAR BLUFF MO. GIVEN RELATIVELY MORE MODEST MASS CONVERGENCE WITH SOUTHWARD EXTENT IN WARM SECTOR...LIKELIHOOD/EXTENT OF CONVECTIVE INITIATION IS QUESTIONABLE PROGRESSIVELY SOUTH. WHILE DETERMINISTIC/ENSEMBLE MODEL GUIDANCE ARE RATHER SCANT WITH CONVECTIVE DEVELOPMENT THIS AFTERNOON...LITTLE OR NO CONVECTIVE INHIBITION EXISTS PER RUC SOUNDINGS...WITH REGION BEING BRUSHED BY IA CLOSED LOW. WILL CONTINUE TO CLOSELY MONITOR DEVELOPMENT TRENDS OVER THE NEXT SEVERAL HOURS...AS MLCAPE OF 750-1000 J/KG AND STRONG VERTICAL SHEAR WOULD FAVOR A SUPERCELL AND LARGE HAIL/TORNADO THREAT GIVEN DEEP CONVECTION. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...LSX...SGF... 38329094 38398830 38528634 37448582 36908687 36698847 36748927 36849060 36969127 37519153 WWWW From Mcd at goshenarc.org Sun Apr 16 20:45:23 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:45:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162043 SWOMCD SPC MCD 162043 INZ000-ILZ000-MOZ000-IAZ000-162215- MESOSCALE DISCUSSION 0529 NWS STORM PREDICTION CENTER NORMAN OK 0343 PM CDT SUN APR 16 2006 AREAS AFFECTED...ERN IA...IL...IND CONCERNING...TORNADO WATCH 193...195... VALID 162043Z - 162215Z SEVERE WEATHER THREAT WILL CONTINUE TO DEVELOP EAST ACROSS ERN IL AND INTO WRN IND OVER THE NEXT FEW HOURS AS OCCLUDED SURFACE LOW REDEVELOPS EWD ALONG WARM FRONT OVER THESE AREAS. AN ARC OF SEVERAL INTENSE SUPERCELLS HAS DEVELOPED OVER THE PAST COUPLE OF HOURS ACROSS THE WARM SECTOR FROM SCNTRL TO CNTRL IL. NEW DEVELOPMENT WAS ALSO OCCURRING WEST OF THE INITIAL BAND OF STORMS...ACROSS LINCOLN...WRN STANFORD..AND EL PASO COUNTIES... INDICATING STRONG ASCENT WAS STILL OCCURRING ACROSS THIS REGION. FORCING AND DEEP SHEAR ACROSS THE REGION WILL CONTINUE TO SUPPORT SUPERCELLS WITH LARGE HAIL. DISCRETE CELLS MOVING INTO BACKED SURFACE FLOW OVER ERN IL WILL CONTINUE TO ENCOUNTER SUFFICIENT LOW LEVEL SHEAR FOR TORNADOES. EVENTUALLY...CELL MERGERS MAY SUPPORT THE EVOLUTION INTO A LARGER SCALE CONVECTIVE COMPLEX. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IWX...IND...PAH...LOT...ILX...LSX...DVN...DMX... 38818533 38528687 38588843 38509026 39609011 40769109 40709218 40619248 41289236 42189222 42109030 41578886 41248816 41058560 WWWW From Mcd at goshenarc.org Sun Apr 16 20:52:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:52:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162051 SWOMCD SPC MCD 162050 INZ000-MIZ000-ILZ000-WIZ000-162215- MESOSCALE DISCUSSION 0530 NWS STORM PREDICTION CENTER NORMAN OK 0350 PM CDT SUN APR 16 2006 AREAS AFFECTED...NORTH CENTRAL/NORTHEAST IL AND FAR SOUTHERN WI/FAR NORTHERN INDIANA CONCERNING...SEVERE THUNDERSTORM WATCH 194... VALID 162050Z - 162215Z VALID PORTION OF SEVERE THUNDERSTORM WATCH 194 CONTINUES UNTIL 00Z...WITH PRIMARY HAZARD OF LARGE HAIL. WELL NORTH OF WARM FRONT ACROSS CENTRAL IL/CENTRAL INDIANA...PRIMARY THREAT FOR LARGE HAIL CONTINUES THROUGH LATE AFTERNOON ACROSS NORTH CENTRAL/NORTHEAST IL INTO FAR SOUTHERN WI/FAR NORTHERN INDIANA. AHEAD OF STACKED LOW OVER SOUTHEAST IA...AMPLE ELEVATED INSTABILITY ABOVE COOL BOUNDARY LAYER WILL CONTINUE TO SUPPORT UPDRAFTS CAPABLE OF LARGE HAIL...WITH MUCAPE UP TO 1000 J/KG ACROSS MUCH OF WW 194 PER RUC SOUNDINGS. HOWEVER...MODEST EFFECTIVE BULK SHEAR AND TENDENCY FOR STORMS TO CLUSTER MAY TEMPER VIGOROUS DEVELOPMENT...ESPECIALLY WITH NORTH/NORTHWEST EXTENT ACROSS WW 194. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...IWX...LOT...MKX...DVN... 42629006 42708828 41678640 41328647 41458771 41618906 41818960 WWWW From Mcd at goshenarc.org Sun Apr 16 23:16:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 19:16:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162314 SWOMCD SPC MCD 162314 INZ000-ILZ000-170115- MESOSCALE DISCUSSION 0531 NWS STORM PREDICTION CENTER NORMAN OK 0614 PM CDT SUN APR 16 2006 AREAS AFFECTED...PORTIONS INDIANA...SRN/ERN IL. CONCERNING...TORNADO WATCH 193...195... VALID 162314Z - 170115Z SEVERE POTENTIAL CONTINUES TO SHIFT EWD FROM ERN IL INTO WRN INDIANA...IN ASSOCIATED WITH LARGE COMPLEX OF TSTMS THAT INCLUDES SEVERAL SUPERCELLS. SRN-MOST OF THIS ACTIVITY -- WITH UNIMPEDED SFC-BASED INFLOW ATTM -- IS STRONGLY RIGHTWARD DEVIANT...CLASSIC/CYCLIC SUPERCELL OVER CRAWFORD COUNTY IL WITH HISTORY OF FUNNEL CLOUDS AND AT LEAST TWO TORNADO REPORTS. THIS TSTM SHOULD MOVE ACROSS WABASH RIVER OVER PORTIONS SULLIVAN/KNOX/DAVIESS/GREENE COUNTIES INDIANA THROUGH 2Z. LARGE HAIL AND TORNADO POTENTIAL ALSO WILL CONTINUE FOR AT LEAST ANOTHER COUPLE HOURS WITH ACTIVITY FARTHER N...MOVING EWD ACROSS IL/INDIANA BORDER. SFC MESOANALYSIS SHOWS OCCLUDED LOW OVER ERN IA...TRIPLE-POINT LOW BETWEEN SPI-PIA...SYNOPTIC WARM FRONT ESEWD FROM LATTER LOW ACROSS IND TO CINCINNATI AREA. MOST CONVECTION SHOULD REMAIN ALONG AND E OF SECONDARY WARM FRONTAL ZONE -- A DIFFERENTIAL HEATING BOUNDARY SEPARATING MORE STRONGLY MIXED BOUNDARY LAYER AIR OF SERN MO/SWRN IL FROM AREAS FORMERLY COVERED IN STRATUS CLOUDS OVER SERN IN/SWRN INDIANA. THIS BOUNDARY -- INITIALLY ANALYZED FROM NEAR SPI TO 20 W EVV -- SHOULD MOVE EWD OUT OF SERN PORTIONS WW 193 SHORTLY. THROUGH 2Z...AIR MASS BETWEEN WARM FRONTS WILL MAINTAIN RELATIVELY LOW LCL...INFLOW-LAYER PARCELS THAT ARE SFC-BASED OR VERY NEARLY SO...AND SOMEWHAT BACKED BOUNDARY LAYER FLOW IN REGION OF LOCALLY MAXIMIZED PRESSURE FALLS. ACCORDINGLY...0-1 KM SRN IS MAXIMIZED OVER SERN IL/SWRN INDIANA AT 250-300 J/KG...WITH EFFECTIVE SHEARS 40-50 KT AND MLCAPES 1000-1500 J/KG. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IWX...IND...PAH...LOT...ILX...LSX...DVN... 38488863 39798907 40768978 41188934 41078793 40918695 40898597 40688561 40118542 39388543 38868558 38578679 WWWW From Mcd at goshenarc.org Mon Apr 17 01:10:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 21:10:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 170109 SWOMCD SPC MCD 170108 INZ000-KYZ000-ILZ000-170245- MESOSCALE DISCUSSION 0532 NWS STORM PREDICTION CENTER NORMAN OK 0808 PM CDT SUN APR 16 2006 AREAS AFFECTED...EXTREME SRN INDIANA//EXTREME N-CENTRAL KY. CONCERNING...HEAVY RAINFALL...TORNADO WATCH 195... VALID 170108Z - 170245Z NARROW CORRIDOR OF SRN INDIANA BETWEEN SRN EDGE OF WW 195 AND OH RIVER WILL BE MONITORED FOR SEVERE POTENTIAL ALONG SRN EDGE OF SEVERE COMPLEX OF TSTMS -- NOW MOVING FROM ERN IL INTO WRN INDIANA. PRIMARY AREA OF CONCERN IS ASSOCIATED WITH HYBRID HP SUPERCELL/BOW ECHO OVER KNOX COUNTY INDIANA...WHICH PRODUCED MEASURED HURRICANE-FORCE GUSTS AND WIND DAMAGE IN ERN CRAWFORD COUNTY IL. THIS ACTIVITY MAY SURVIVE LONG ENOUGH TO MOVE OUT OF SRN-MOST COUNTIES IN WW...AND ACROSS PORTIONS ORANGE/WASHINGTON COUNTIES...TOWARD NWRN/NRN FRINGES SDF METRO AREA. MODIFIED RUC SOUNDINGS INDICATE SIGNIFICANT INCREASE IN SBCINH WITH SWD EXTENT ACROSS SWRN/S-CENTRAL INDIANA INTO ADJACENT PORTION NRN KY. BOUNDARY LAYER ALSO IS EXPECTED TO DESTABILIZE GRADUALLY OVER NEXT FEW HOURS BECAUSE OF DIABATIC SFC COOLING. THEREFORE THERE IS CONSIDERABLE PROBABILITY THAT TSTMS MAY NOT SURVIVE AS FAR AS SDF AREA. HOWEVER...SOME POTENTIAL EXISTS FOR STRONG CONVECTIVE-SCALE LIFT TO SUSTAIN THIS ACTIVITY -- SUCH AS STRONG FORCED ASCENT PROVIDED BY LEADING EDGE OF OUTFLOW SLAB. VERTICAL SHEAR PROFILES WILL REMAIN AT LEAST MARGINALLY FAVORABLE...MAINLY IN TERMS OF BOUNDARY LAYER SRH BECAUSE OF STRONG TURNING WITH HEIGHT IN LOW LEVELS. ADDITIONALLY...EXPECT TRAINING OF CORES PRODUCING 2-3 INCH/HOUR RAINFALL RATES ALONG SWRN INDIANA CORRIDOR BETWEEN KNOX/SULLIVAN COUNTIES...BMG AREA AND ORANGE COUNTY. ..EDWARDS.. 04/17/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...ILX... 38708827 39008773 39448712 39498654 39418582 39048557 38598560 38298563 38198579 38118627 38348757 WWWW From Mcd at goshenarc.org Mon Apr 17 04:45:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 00:45:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 170443 SWOMCD SPC MCD 170443 NDZ000-MTZ000-170645- MESOSCALE DISCUSSION 0533 NWS STORM PREDICTION CENTER NORMAN OK 1143 PM CDT SUN APR 16 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/NERN MT...EXTREME NWRN ND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 170443Z - 170645Z BAND OF TSTMS -- NOW MOVING NNEWD NEARLY 40 KT ACROSS SRN MCCONE COUNTY -- SHOULD MOVE TOWARD PORTIONS RICHLAND/ROOSEVELT/DANIELS COUNTIES DURING NEXT 2-3 HOURS. THIS ACTIVITY ALSO MAY BUILD/PROPAGATE NEWD INTO ZONE OF FAVORABLE ELEVATED WAA...AND MAY CLIP NWRN CORNER OF ND. THOUGH INFLOW LAYER APPEARS TO BE ELEVATED WELL AGL...SOME OF THIS ACTIVITY MAY PRODUCE DAMAGING SFC GUSTS AS WELL AS HAIL. WW NOT ANTICIPATED GIVEN LIMITED AREA AND TIME OF SEVERE POTENTIAL. VWP DATA AND MODEL SOUNDINGS INDICATE STRONG VEERING WITH HEIGHT AND LOW LEVEL WAA PROFILE ACROSS THIS REGION...WITH MOISTENING IN 650-800 MB LAYER WHERE EFFECTIVE INFLOW IS ESTIMATED. ELEVATED MUCAPES UP TO ABOUT 500 J/KG ARE EXPECTED TO CONTINUE JUST AHEAD OF THIS CONVECTION. THOUGH CONVECTIVELY STABLE...AIR MASS FROM SFC-800 MB ALSO IS RELATIVELY DRY AND SUPPORTS DCAPE VALUES COMPARABLE TO LARGEST MUCAPES...BASED ON MODIFIED RUC SOUNDINGS. GIVEN THAT FACTOR AND SHAPE OF WET BULB PROFILE IN SUBCLOUD LAYER. ISOLATED 58 KT GUST WAS REPORTED IN ROSEBUD COUNTY FROM THIS ACTIVITY...AND OCNL DAMAGING GUSTS MAY CONTINUE TO PENETRATE BOUNDARY LAYER AND REACH SFC. ..EDWARDS.. 04/17/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...GGW... 47220543 47440581 47530615 47580630 48990574 48980347 47290517 WWWW From Mcd at goshenarc.org Tue Apr 18 00:36:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 20:36:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 180033 SWOMCD SPC MCD 180033 NDZ000-SDZ000-MTZ000-WYZ000-180200- MESOSCALE DISCUSSION 0540 NWS STORM PREDICTION CENTER NORMAN OK 0733 PM CDT MON APR 17 2006 AREAS AFFECTED...PORTIONS EXTREME NERN WY...WRN SD...SWRN ND CONCERNING...SEVERE THUNDERSTORM WATCH 198... VALID 180033Z - 180200Z BAND OF SEVERE TSTMS WILL MOVE NEWD FROM HARDING COUNTY SD INTO BOWMAN COUNTY ND WITHIN NEXT HOUR...WITH POTENTIAL FOR SEVERE HAIL/GUSTS. ADDITIONAL/ISOLATED TSTMS ARE MOVING NWD INTO SRN HARDING COUNTY AND DEVELOPING FARTHER SW INVOF SD/WY BORDER. MIDLEVEL CONVECTION OVER ERN WY IS ASSOCIATED WITH BAND OF ENHANCED LARGE SCALE ASCENT MOVING EWD AHEAD OF INTENSE NRN ROCKIES/NRN GREAT BASIN TROUGH ALOFT. THIS ACTIVITY IS CHARACTERIZED BY INCREASING CG LIGHTNING...BUILDING REFLECTIVITIES...AND COOLING IR CLOUD TOPS. BOUNDARY LAYER ACROSS SRN PORTIONS WW...AND REMAINDER SWRN SD...REMAINS RELATIVELY DRY WITH SFC DEW POINTS MID 40S ON PLAINS AND 30S IN BLACK HILLS. HOWEVER...MOIST ADVECTION AND STRENGTHENING LLJ MAY RESULT IN SOME OF THIS ACTIVITY BECOMING ROOTED NEAR SFC. MODIFIED 00Z RAP RAOB AND RUC SOUNDINGS INDICATE WELL MIXED SUBCLOUD LAYER CONDUCIVE TO MAINTAINING SEVERE DOWNDRAFTS AND HAIL TO SFC...IN FAVORABLE VERTICAL SHEAR PROFILES FOR BOTH SUPERCELLS AND BOW FORMATIONS. 53 KT GUST AND THREE REPORTS OF .75-1.75 INCH HAIL HAVE BEEN RECEIVED COMBINED AS OF 0030Z...OVER HARDING/BOWMAN COUNTIES. THIS REPRESENTS STRONG CLIMATOLOGICAL ANOMALY. SPC SEVERE DATABASE INDICATES THESE ARE FIRST RECORDED APRIL SEVERE EVENTS IN THEIR COUNTIES...AND HALF THE TOTAL OF EIGHT APRIL REPORTS FOR ALL COUNTIES IN WW...SINCE RECORDS BEGAN IN 1950. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...UNR...BYZ... 44160252 44180435 47050357 47060168 WWWW From Mcd at goshenarc.org Tue Apr 18 03:27:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 23:27:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 180325 SWOMCD SPC MCD 180325 SDZ000-180500- MESOSCALE DISCUSSION 0541 NWS STORM PREDICTION CENTER NORMAN OK 1025 PM CDT MON APR 17 2006 AREAS AFFECTED...PORTIONS WRN SD. CONCERNING...SEVERE THUNDERSTORM WATCH 198... VALID 180325Z - 180500Z SEVERE TSTM POTENTIAL IS EXPECTED TO DIMINISH THROUGH REMAINDER EVENING ACROSS WW AREA...THOUGH ISOLATED HAIL/GUSTS NEAR SEVERE LEVELS MAY STILL OCCUR PARTICULARLY OVER ERN HALF OF ORIGINAL WW...SWD ACROSS PENNINGTON COUNTY PLAINS TO NEAR NEB BORDER. ND ALREADY HAS BEEN REMOVED FROM WW AND REMAINING PORTIONS IN SD PORTION MAY BE ALLOWED TO EXPIRE AS SCHEDULED. MERIDIONAL BAND OF TSTMS WILL CONTINUE SHIFTING EWD ACROSS THIS REGION...WHILE EMBEDDED CELLS AND LINE SEGMENTS MOVE NNEWD 30-40 KT. ONE SUCH BAND IS EVIDENT ATTM OVER ERN CUSTER/NWRN SHANNON COUNTY...HEADED FOR CENTRAL/ERN PORTIONS OF BOTH PENNINGTON AND MEADE COUNTIES. PRONOUNCED OUTFLOW BOUNDARY HAS SURGED WELL E OF CONVECTIVE BAND...FURTHER STABILIZING NEAR-SFC LAYER BEYOND AMBIENT DIABATIC COOLING RATES. STILL...MODIFIED RAOBS AND RUC SOUNDINGS SHOW LARGE SUBCLOUD DEW POINT DEPRESSIONS ABOVE STABLE OUTFLOW LAYER -- REMNANTS OF EARLIER/DEEPLY-MIXED BOUNDARY LAYER AIR MASS. THIS MAY SUPPORT POTENTIAL FOR ISOLATED DAMAGING GUSTS TO REACH SFC...AS WELL AS LARGE HAIL...FROM MOST VIGOROUS CONVECTION. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ABR...UNR... 44200367 45930322 45920195 43020210 43000333 WWWW From Mcd at goshenarc.org Tue Apr 18 17:33:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 13:33:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 181731 SWOMCD SPC MCD 181730 FLZ000-GAZ000-ALZ000-181930- MESOSCALE DISCUSSION 0542 NWS STORM PREDICTION CENTER NORMAN OK 1230 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS OF ERN AL...SWRN GA AND THE FLA PANHANDLE CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 181730Z - 181930Z ISOLATED SVR TSTMS MAY OCCUR ALONG A STATIONARY BOUNDARY EXTENDING FROM ECENTRAL AL SWD INTO SWRN GA AND ERN FLA PANHANDLE BY 20Z. AREA WILL BE MONITORED FOR A POSSIBLE WW. 17Z VIS SAT IMAGERY SHOWS TOWERING CU ALONG A BOUNDARY THAT EXTENDED ROUGHLY FROM 25 E BHM TO 40 W ABY TO 15 E TLH. DESPITE VERY WEAK TO MINIMAL CINH REMAINING PER MODIFIED 12Z BMX AND RECENT RUC SOUNDINGS...WEAK CONVERGENCE HAS AS YET PREVENTED TSTM DEVELOPMENT. THE GREATEST PROBABILITY FOR INITIAL TSTM DEVELOPMENT IS OVER THE FAR SWRN GA/ERN FLA PANHANDLE WHERE CONVERGENCE WAS SLIGHTLY GREATER AS ANOTHER BOUNDARY MOVES WWD ACROSS THE AREA AND INTERSECTS THE INITIAL STATIONARY BOUNDARY. REGARDLESS...GIVEN CONTINUED DAYTIME HEATING AND DESTABILIZATION AT LEAST ISOLATED TSTM DEVELOPMENT IS EXPECTED ALONG THE MAIN STATIONARY BOUNDARY BY 20Z. ALTHOUGH 1-4 KM FLOW REMAINS RATHER WEAK PER RECENT VWP DATA...MODERATE NWLY 4-9 KM FLOW /STRONGEST ABOVE 6 KM/ MAY BE SUFFICIENTLY STRONG TO FAVOR STORM TOP VENTILATION. COMBINED WITH WEAK ELY FLOW ON THE EAST SIDE OF THE STATIONARY BOUNDARY...SOME STORM ROTATION APPEARS LIKELY. ALTHOUGH LAPSE RATES INITIALLY ARE RELATIVELY POOR /6-6.5 DEG C/KM / SLIGHT MID LVL COOLING SHOULD AID IN STEEPENING LAPSE RATES THROUGH THE AFTERNOON. WITH MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG / MARGINALLY SVR HAIL WILL BE POSSIBLE. ADDITIONALLY...STEEP LOW LEVEL LAPSE RATES /25 DEG T/TD SPREADS AT THE SFC/ MAY SUPPORT DMGG WIND GUSTS AS WELL. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...MOB... 31648422 32898534 33738608 33638653 32648656 31368589 30558533 30268476 30178385 30678348 WWWW From Mcd at goshenarc.org Tue Apr 18 20:07:53 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 16:07:53 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182005 SWOMCD SPC MCD 182005 TXZ000-182200- MESOSCALE DISCUSSION 0544 NWS STORM PREDICTION CENTER NORMAN OK 0305 PM CDT TUE APR 18 2006 AREAS AFFECTED...TX HILL COUNTRY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182005Z - 182200Z ISOLATED SVR TSTMS MAY DEVELOP BY 22Z OVER THE WRN PORTIONS OF THE TX HILL COUNTRY FROM EDWARDS COUNTY NEWD TOWARDS LLANO COUNTY. GIVEN THE MARGINAL NATURE OF THE THREAT EXPECTED...A WW IS NOT ANTICIPATED ATTM. LATEST VISIBLE SAT IMAGERY SHOWS TOWERING CU ALONG A DRYLINE FROM EDWARDS COUNTY NEWD INTO MASON COUNTY. TEMPERATURES HAVE WARMED INTO THE MID-UPPER 90S ACROSS THE HILL COUNTRY WITH DEWPTS IN THE 50S. DESPITE THE LOW DEWPTS...MODERATE INSTABILITY WAS REALIZED WITH MLCAPES AROUND 1500 J/KG. ENOUGH CINH REMAINS AT 19Z /75-100 J/KG / THAT TSTM DEVELOPMENT WILL LIKELY TAKE A FEW MORE HRS TO OCCUR. DESPITE THE WEAK LOW LEVEL CONVERGENCE...A SUBTLE MID LEVEL WAVE SEEN ON WV IMAGERY OVER NRN MX MAY SUPPORT SOME LARGE SCALE LIFT. A DEEP MIXED LAYER BENEATH MODERATE INSTABILITY /DCAPES AROUND 1500 J/KG / AND STEEP LAPSE RATES UP TO 10 KFT MAY SUPPORT DMGG WIND GUSTS WITH THE STRONGEST TSTMS. DESPITE STEEP MID LEVEL LAPSE RATES AND MODERATE MID LEVEL SHEAR...VERY WARM TEMPERATURES IN THE LOW LEVELS WILL LIKELY KEEP ANY HAIL TO MARGINAL LVLS. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX...SJT... 30729879 30459974 30180006 29770031 29450018 29209966 29299940 29539866 29959808 30579800 30879820 WWWW From Mcd at goshenarc.org Tue Apr 18 21:08:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 17:08:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182106 SWOMCD SPC MCD 182106 ALZ000-TNZ000-182300- MESOSCALE DISCUSSION 0545 NWS STORM PREDICTION CENTER NORMAN OK 0406 PM CDT TUE APR 18 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182106Z - 182300Z ISOLATED SVR TSTMS WILL BE POSSIBLE ALONG A STATIONARY BOUNDARY ACROSS NRN AL NWD INTO SRN MIDDLE TN. AREA WILL BE MONITORED FOR A POSSIBLE WW. DESPITE UPPER LEVEL RIDGING...ISOLATED CONVECTION HAS DEVELOPED OVER NRN AL ALONG STATIONARY SFC BOUNDARY. ALTHOUGH LOW LEVEL FLOW WAS RELATIVELY WEAK...MID LEVEL NWLY FLOW FROM 30-40 KTS AND MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG/ ARE FAVORABLE FOR AT LEAST AN ISOLATED SVR THREAT. DEGREE OF ADDITIONAL INITIATION REMAINS UNCERTAIN GIVEN LACK OF SAT DATA AND WEAK SYNOPTIC-MESOSCALE FORCING. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN... 34828572 36028710 35768768 35358781 34528761 33818659 33508595 33738550 33878549 WWWW From Mcd at goshenarc.org Tue Apr 18 22:48:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 18:48:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182246 SWOMCD SPC MCD 182245 MOZ000-190045- MESOSCALE DISCUSSION 0546 NWS STORM PREDICTION CENTER NORMAN OK 0545 PM CDT TUE APR 18 2006 AREAS AFFECTED...MO. CONCERNING...TORNADO WATCH 199... VALID 182245Z - 190045Z DEEP CB DEVELOPMENT NOW EVIDENT OVER NWRN AND SWRN PORTIONS WW...SPECIFICALLY FROM SZL AREA NWWD TOWARD GENTRY COUNTY. ADDITIONAL TOWERS ARE EVIDENT ON VIS IMAGERY OVER HICKORY COUNTY. EXPECT CONVECTION TO FILL IN BETWEEN THESE AREAS DURING NEXT 1-2 HOURS. OPTIMAL COMBINATION OF BUOYANCY AND SHEAR APPEARS TO BE IN AIR MASS BETWEEN MKC-COU...SEWD ACROSS CENTRAL MO. TSTMS FARTHER NW MAY DEVELOP SUPERCELL CHARACTERISTICS BUT WILL LIFT NEWD OVER RELATIVELY STABLE AIR MASS NEAR IA/MO BORDER. 22Z SFC MESOANALYSIS SHOWS OCCLUDED FRONT FROM NWRN CORNER IA SSEWD OVER CLINTON/RAY COUNTIES MO...WHERE WARM/COLD FRONTAL OCCLUSION IS PROPAGATING SEWD ATTM. COLD FRONT EXTENDS SWWD TO VICINITY JLN AND SHOULD CONTINUE MOVING EWD 15-20 KT. WARM FRONT -- ANALYZED FROM RAY COUNTY SEWD PAST VIH TO VICINITY WRN TIP OF KY...LIFTING NEWD APPROXIMATELY 10 KT. WEAK MESOLOW IS EVIDENT INVOF SZL..ALONG CONFLUENCE LINE THAT IS ANALYZED FROM NEAR OCCLUSION POINT SSEWD TO NEAR SGF. OCCLUDED/COLD FRONTS AND CONFLUENCE LINE ALSO ARE EVIDENT IN EAX REFLECTIVITY LOOPS AS FINE LINES. PRIMARY AREAS OF DEVELOPMENT SHOULD REMAIN ALONG OCCLUDED FRONT N OF I-70. FARTHER S...ACTIVITY SHOULD FORM MAINLY ALONG CONFLUENCE LINE...PARTICULARLY AS COLD FRONT MERGES AND ENHANCES BOUNDARY LAYER CONVERGENCE. VERTICAL SHEAR PROFILES WILL BE FAVORABLE E OF CONFLUENCE LINE WHERE SLY/SSELY FLOW IS PRESENT...AND EVEN MORE FAVORABLE ALONG WARM FRONT. ACCORDINGLY...0-3 KM SRH RANGES FROM LESS THAN 100 J/KG BETWEEN COLD FRONT AND CONFLUENCE LINE TO 200-300 J/KG ALONG AND E OF WARM FRONT...WHERE DEEP-LAYER SHEAR ALSO IS MAXIMIZED. MODIFIED 21Z SGF RAOB AND RUC SOUNDINGS SHOW STEEP MIDLEVEL LAPSE RATES OF 8-9 DEG C/KM SUPPORTING MLCAPES 3000-3500 J/KG...NEAR AND SE OF MESOLOW. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...SGF...EAX... 37539110 37549365 40549488 40539224 WWWW From Mcd at goshenarc.org Tue Apr 18 23:17:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:17:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182315 SWOMCD SPC MCD 182314 ARZ000-LAZ000-TXZ000-OKZ000-190115- MESOSCALE DISCUSSION 0547 NWS STORM PREDICTION CENTER NORMAN OK 0614 PM CDT TUE APR 18 2006 AREAS AFFECTED...FAR SERN OK...NERN TX...SWRN AR AND NWRN LA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182314Z - 190115Z NON-SURFACE BASED CONVECTION HAS DEVELOPED RECENTLY OVER NERN TX BENEATH HIGH CLOUD COVER. IT IS UNCERTAIN ATTM WHETHER CONVECTION CAN BECOME SURFACE BASED IN THE NEXT HR OR TWO BEFORE INCREASING BOUNDARY LAYER INHIBITION OCCURS. AREA WILL BE MONITORED FOR A POSSIBLE WW. RECENT SFC OBS FROM DFW HAD BKN150 AND WEBCAMS IN THE DFW AREA SUGGEST THAT A MID LEVEL ACCAS BAND WITH SOME VIRGA WAS MOVING ACROSS THE REGION IN ASSOCIATION WITH MID/HIGH LEVEL SPEED MAX. SUFFICIENT MID LEVEL MOISTENING HAS LIKELY OCCURRED WITH THIS VIRGA/ACCAS TO ALLOW FOR ELEVATED CONVECTION TO DEVELOP OVER NERN TX. SURFACE OBSERVATIONS OVER THE ARKLATEX REGION AHEAD OF THIS CONVECTION...MODIFIED FOR 21Z RUC FORECAST SOUNDINGS...SUGGEST THAT AROUND 100 J/KG OF MLCINH REMAINS. GIVEN RECENT OBSERVED CELL MOTION ON RADAR...IT APPEARS CONVECTION REMAINS NON-SURFACE BASED. THIS BEING SAID...IT REMAINS POSSIBLE THAT SUFFICIENT EVAPORATIVE COOLING MIGHT OCCUR IN THE NEXT HR OR TWO /WHILE THE BOUNDARY LAYER HAS THE LEAST CINH/ THAT THIS CONVECTION COULD STILL BECOME SURFACE BASED. MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG / AND SUFFICIENT SHEAR WILL ALLOW FOR A SVR WIND/HAIL THREAT IF STORMS DO BECOME SURFACE BASED. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...FWD... 33999438 33519537 32949517 32589459 32469384 32969293 33899262 WWWW From Mcd at goshenarc.org Tue Apr 18 23:30:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:30:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182328 SWOMCD SPC MCD 182327 IAZ000-190100- MESOSCALE DISCUSSION 0548 NWS STORM PREDICTION CENTER NORMAN OK 0627 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/SRN IA. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182327Z - 190100Z SEVERE POTENTIAL IS INCREASING ACROSS PORTIONS CENTRAL/SRN IA. AREA IS BEING MONITORED FOR POSSIBLE WW. SFC MESOANALYSIS SHOWS OCCLUDED FRONT NEAR LINE FROM 20 N FSD...50 W DSM...35 NE STJ. THIS FRONT SHOULD FORM CONTINUE MOVING EWD 15-20 KT ACROSS WRN IA...DENOTING WRN EDGE OF SIGNIFICANT CONVECTIVE POTENTIAL. DISCRETE AND POTENTIALLY SUPERCELLULAR TSTMS HAVE FORMED OVER NWRN MO PORTION OF FRONT...IN NRN PORTIONS WW 199...WITH ADDITIONAL DEVELOPMENT POSSIBLE FARTHER N. ALTHOUGH MODIFIED RUC SOUNDINGS INDICATE STRONG SBCINH...FAVORABLE MUCAPES AND VERTICAL SHEAR PROFILES ARE EVIDENT IN PROFILER DATA AND MODIFIED RAOBS. EXPECT AT LEAST FEW SEVERE TSTMS TO MOVE NEWD ACROSS THIS AREA ALONG/AHEAD OF FRONT. MOST PROBABLE NEAR-TERM RISK WILL BE ACROSS PORTIONS DECATUR/WAYNE/LUCAS/MONROE/APPANOOSE COUNTIES...INVOF PROJECTED TRACKS OF MO TSTMS. MAIN THREAT IS LARGE HAIL. PROSPECTIVE INFLOW LAYER WILL BECOME PROGRESSIVELY MORE ELEVATED WITH NWD EXTENT...INDICATING DIMINISHING WIND/TORNADO POTENTIAL NWD ACROSS DISCUSSION AREA. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DVN...DMX... 40609411 41239431 41709430 42199414 42499371 42439315 42159275 41309245 40609225 WWWW From Mcd at goshenarc.org Tue Apr 18 23:52:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:52:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182350 SWOMCD SPC MCD 182349 WIZ000-MNZ000-190215- MESOSCALE DISCUSSION 0549 NWS STORM PREDICTION CENTER NORMAN OK 0649 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN MN...EXTREME WRN WI. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182349Z - 190215Z BAND OF SCATTERED TSTMS SHOULD MAINTAIN RISK FOR OCNL/MRGL SEVERE HAIL AS IT MOVES NWD TO NNEWD ACROSS MN AND PERHAPS WRN TIER WI COUNTIES N RST. WW NOT ANTICIPATED ATTM. SFC ANALYSIS SHOWS OCCLUDED FRONT EXTENDING FROM S-CENTRAL SD CYCLONE SEWD ACROSS PIPESTONE COUNTY MN...INTO W-CENTRAL IA. ELEVATED BAND OF LIFT HAS CONTRIBUTED TO TSTM DEVELOPMENT PARALLEL TO AND ABOUT 100 NM NE OF SFC FRONT. MOST INTENSE ACTIVITY AS OF WAS LOCATED FROM MEEKER-WASECA COUNTIES...HOWEVER INTENSIFICATION IS POSSIBLE SEWD TOWARD RST AREA AND SOMEWHAT NWWD TOWARD DOUGLAS/TODD COUNTIES. VWP/PROFILER DATA SHOWS ROUGHLY 40 KT SELY LLJ AROUND 850 MB LEVEL OVER THIS REGION. ELEVATED WAA/MOIST ADVECTION INTO AREA N AND E OF CONVECTIVE BAND WILL SUPPORT ELEVATED MUCAPES ROUGHLY 1000 J/KG...WITH STEEP MIDLEVEL LAPSE RATES OF 8-9 DEG C/KM. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DLH...ARX...MPX...FGF... 43519290 44899433 45519515 45809529 46969503 46599366 45989279 45589248 44849210 WWWW From Mcd at goshenarc.org Wed Apr 19 00:52:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 20:52:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190050 SWOMCD SPC MCD 190050 TXZ000-190245- MESOSCALE DISCUSSION 0550 NWS STORM PREDICTION CENTER NORMAN OK 0750 PM CDT TUE APR 18 2006 AREAS AFFECTED...SCENTRAL/CENTRAL TX CONCERNING...SEVERE THUNDERSTORM WATCH 200... VALID 190050Z - 190245Z CLUSTER OF SVR STORMS OVER THE HILL COUNTRY WILL MOVE EWD AROUND 25 KTS INTO THE I-35 CORRIDOR FROM GEORGETOWN SWD THROUGH AUS OVER THE NEXT FEW HRS. INCREASING INHIBITION WILL LIKELY LIMIT ADDITIONAL SVR TSTM DEVELOPMENT TO THE WSW OF THIS ACTIVITY. THERFORE THE SVR TSTM THREAT APPEARS TO BE DECREASING OVER THE OVER THE SRN/WRN HILL COUNTRY /REAL...BANDERA...MEDINA...UVALDE... AND BEXAR COUNTIES/. THIS AREA IS EXPECTED TO BE CLEARED WITHIN THE NEXT HR. OBSERVED CONDITIONS OVER THE ERN HILL COUNTRY ENTERED INTO THE 00Z DRT SOUNDING INDICATES AROUND 100 J/KG OF MUCINH. WITH THE COMBINATION OF STORMS MOVING OVER LOWER ELEVATION AND INCREASING CINH AS BOUNDARY LAYER DECOUPLES OVER THE NEXT FEW HRS...EXPECT A GRADUALLY WANING SVR THREAT WITH CLUSTER OF STORMS OVER THE ERN/NRN HILL COUNTRY. HOWEVER BEFORE THAT OCCURS...LARGE HAIL/DMGG WINDS WILL REMAIN POSSIBLE THROUGH AT LEAST 02Z. NO ADDITIONAL WW IS EXPECTED EAST OF WW 200 FOR THE ABOVE REASONING. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT... 30779824 30419959 30049965 29529927 29779827 30459705 31019716 WWWW From Mcd at goshenarc.org Wed Apr 19 02:01:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 22:01:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190159 SWOMCD SPC MCD 190159 ILZ000-MOZ000-IAZ000-190330- MESOSCALE DISCUSSION 0551 NWS STORM PREDICTION CENTER NORMAN OK 0859 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS NRN/ERN MO....WRN IL. CONCERNING...TORNADO WATCH 199... VALID 190159Z - 190330Z ONE OR TWO WWS MAY BE REQUIRED E OF PRESENT WW AREA...COVERING PORTIONS MO/IL NEAR MS RIVER. BROKEN BAND OF STRONG AND SEVERE TSTMS WILL CONTINUE TO SHIFT EWD ACROSS CENTRAL/NERN MO...THEN ACROSS MS RIVER OVER PORTIONS WRN IL. SFC MESOANALYSIS SHOWS OCCLUDED FRONT FROM JUST SW DSM SSEWD TO NEAR COU...WHERE INTENSE CLUSTER OF TSTMS APPEARS TO COINCIDE WITH MESOLOW/TRIPLE POINT. WARM FRONT EXTENDS SEWD FROM THAT AREA TO NEAR SRN TIP OF IL...AND SHOULD LIFT NEWD ABOUT 10 KT. OCCLUDED/COLD FRONT WILL CONTINUE MOVING EWD 20-25 KT ACROSS CENTRAL MO. THIS WILL PRODUCE ESEWD-PROPAGATING ZIPPER EFFECT FOR TRIPLE POINT TOWARD AREA NEAR OR JUST SW STL. VERTICAL SHEAR PROFILES WILL REMAIN FAVORABLE FOR BOTH SUPERCELLS AND BOW ECHOES. RUC SOUNDINGS OVER ERN MO NEAR WARM FRONT...AND VWP FROM STL AREA...ON COOL SIDE OF WARM FRONT -- ARE QUITE FAVORABLE WITH 0-3 KM SRH 300-500 J/KG. TORNADO/DAMAGING WIND POTENTIAL SHOULD BE MAXIMIZED AROUND OCCLUSION TRIPLE POINT REGION AND SLGTLY SEWD ALONG WARM FRONT. BOUNDARY LAYER AIR MASS SW OF WARM FRONT WILL STABILIZE GRADUALLY THROUGH REMAINDER EVENING...HOWEVER MODIFIED RUC SOUNDINGS SUGGEST EFFECTIVE PARCELS IN WARM SECTOR WILL REMAIN ROOTED NEAR SFC FOR SEVERAL MORE HOURS. MAIN THREAT N OF TRIPLE POINT WILL BE HAIL...WHERE BUOYANCY IS ROOTED AGL. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...ILX...LSX...DVN...SGF...EAX... 37549252 38659239 39739284 40359357 40509339 40549195 40589077 40269045 39909016 39248983 38648962 38058959 37648966 37429018 WWWW From Mcd at goshenarc.org Wed Apr 19 02:46:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 22:46:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190243 SWOMCD SPC MCD 190243 ARZ000-LAZ000-TXZ000-OKZ000-190445- MESOSCALE DISCUSSION 0552 NWS STORM PREDICTION CENTER NORMAN OK 0943 PM CDT TUE APR 18 2006 AREAS AFFECTED...MUCH OF CENTRAL AR / FAR SERN OK AND NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 190243Z - 190445Z A GRADUAL INCREASE IN DEEP CONVECTION IS ANTICIPATED ALONG THE COLD FRONT THROUGH THE EVENING. LARGE HAIL WOULD BE THE MAIN SEVERE THREAT. RADAR ECHOES CONTINUE TO INCREASE ACROSS WRN AR ALONG COLD FRONT. 00Z LZK SOUNDING SHOWS VERY STEEP MID LEVEL LAPSE RATES IN PLACE. STRONG INSTABILITY EXISTS WHEN MODIFIED FOR MID 60S BOUNDARY LAYER DEWPOINTS AS SEEN ON UPSTREAM SHV SOUNDING. SOME CAPPING EXISTS...BUT DEEP MOISTURE CONVERGENCE ALONG COLD FRONT SHOULD BE ENOUGH TO GET AT LEAST ISOLATED SVR CONVECTION GOING. AREA VWPS INDICATE STRONG LOW LEVEL WARM ADVECTION PROFILE WHICH WILL MAINTAIN FEED OF HIGHER THETA-E AIR INTO THE FRONTAL ZONE. ..JEWELL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SHV...TSA...FWD... 35509348 35999287 36329196 36489136 36299067 35719070 34609180 33389297 32949402 32739476 32789542 33169600 33599595 34109517 WWWW From Mcd at goshenarc.org Wed Apr 19 03:39:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 23:39:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190337 SWOMCD SPC MCD 190336 ILZ000-IAZ000-MOZ000-190530- MESOSCALE DISCUSSION 0553 NWS STORM PREDICTION CENTER NORMAN OK 1036 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN IA...W-CENTRAL/NWRN IL...NERN MO. CONCERNING...SEVERE THUNDERSTORM WATCH 201...202... VALID 190336Z - 190530Z SEVERE TSTM POTENTIAL --- PRIMARILY LARGE HAIL WITH ISOLATED DAMAGING WIND -- SHOULD CONTINUE TO SHIFT EWD ACROSS WWS AND MAY EXTEND EWD INTO EXTREME ERN IA AND NWRN IL. SEVERAL REPORTS OF MAINLY 1 INCH AND SMALLER DIAMETER HAIL HAVE BEEN RECEIVED OVER WWS DURING PAST 1-2 HOURS. SINCE HAIL THREAT SHOULD REMAIN MRGLLY SEVERE...AND LIKELY NOT AS NUMEROUS AS FARTHER W ACROSS NRN MO AND IA...WW NOT PLANNED ATTM. HOWEVER...WILL CONTINUE TO MONITOR. TWO PRIMARY BANDS OF CONVECTION ARE EVIDENT AS OF 315Z...FIRST FROM NWRN PORTIONS WW 213 NWD TO NEAR UIN/BRL. THIS ACTIVITY WILL MOVE E OF WWS SHORTLY...WITH POTENTIAL FOR ISOLATED HAIL NEAR SEVERE LEVELS. TSTMS IN OTHER BAND -- GENERALLY BETWEEN MCW AND 20 SW IRK -- WILL MOVE NEWD ACROSS REMAINDER WRN/NRN PORTIONS WW 201...AND FROM NERN PORTIONS WW 199 INTO SERN IA AND EXTREME NERN MO. MODIFIED RUC FCST SOUNDINGS SHOW FAVORABLE THERMODYNAMIC PROFILES OVER SRN IA/IL BORDER REGION...AMIDST STRONG LOW LEVEL WAA PROFILES. EXPECT 8-9 DEG C/KM MIDLEVEL LAPSE RATES...AND MUCAPES AROUND 1500 J/KG...WITH BUOYANCY ROOTED IN 750-850 MB LAYER. HOWEVER...RELATIVELY WEAK MIDLEVEL WINDS CONTRIBUTE TO ONLY 20-30 KT EFFECTIVE SHEARS...WITH LIMITED POTENTIAL FOR WELL-ORGANIZED LARGE HAIL EVENT. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...DMX...EAX... 38889144 39359154 40479216 40509309 41439330 42009390 42739379 42739248 42189080 41508970 40378960 39098984 WWWW From Mcd at goshenarc.org Wed Apr 19 05:03:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 01:03:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190501 SWOMCD SPC MCD 190500 ILZ000-MOZ000-190600- MESOSCALE DISCUSSION 0554 NWS STORM PREDICTION CENTER NORMAN OK 1200 AM CDT WED APR 19 2006 AREAS AFFECTED...PORTIONS ERN MO...CENTRAL/SRN IL. CONCERNING...TORNADO WATCH 203... VALID 190500Z - 190600Z PRIMARY SEVERE POTENTIAL WILL REMAIN ASSOCIATED WITH LONG-LIVED/COMPLEX CLUSTER OF SEVERE TSTMS MOVING ESEWD FROM JEFFERSON COUNTY MO. PORTIONS STE. GENEVIEVE/PERRY COUNTIES MO...AND MONROE/RANDOLPH/JACKSON/PERRY COUNTIES IL ARE IN PATH OF THIS ACTIVITY...WHICH CONTINUES TO POSE RISK OF DAMAGING GUSTS...HAIL AND POSSIBLY A TORNADO OR TWO. CONVECTION SHOULD REMAIN LOCATED INVOF OCCLUSION TRIPLE POINT WHERE MOIST BUOYANT PARCELS ARE LOCATED...AS WELL AS MAXIMIZED LOW LEVEL HODOGRAPHS. FARTHER E AND NE ACROSS PORTIONS CENTRAL/SRN IL...ELEVATED MUCAPES AROUND 1000 J/KG ARE EVIDENT...BASED ON MODIFIED RAOBS AND RUC SOUNDINGS. THIS WILL CONTINUE TO SUPPORT SCATTERED TSTMS WITH OCCASIONAL HAIL...THROUGH VERTICAL SHEAR PROFILES IN LOW-MIDLEVELS OF BUOYANT LAYER SHOULD REMAIN RELATIVELY WEAK. MEANWHILE...GUST FRONT HAS MOVED WELL AHEAD OF MOST REFLECTIVITY CORES ASSOCIATED WITH W-CENTRAL IL LINE...BUT STILL PRODUCED MEASURED 51 KT GUST AT IJX OB AT 425Z. EXPECT DAMAGING WIND POTENTIAL WITH THIS GUST FROM TO DIMINISH WITH EWD EXTENT INTO PROGRESSIVELY MORE STABLE BOUNDARY LAYER...AND AS PARENT CONVECTION REMAINS REMOVED BY SEVERAL MILES OR MORE FROM LEADING EDGE OF OUTFLOW. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...ILX...LSX... 37079080 37399062 38259075 39059001 39458886 39388780 38928761 37888834 37158929 WWWW From Mcd at goshenarc.org Wed Apr 19 06:42:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 02:42:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190640 SWOMCD SPC MCD 190640 SDZ000-NDZ000-MTZ000-WYZ000-191245- MESOSCALE DISCUSSION 0555 NWS STORM PREDICTION CENTER NORMAN OK 0140 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN MT AND THE BLACK HILLS REGION CONCERNING...HEAVY SNOW AND NEAR BLIZZARD CONDITIONS VALID 190640Z - 191245Z HEAVY SNOW IS EXPECTED THROUGH THE NIGHT WITH HRLY RATES OF AT LEAST 1 IN/HR. STRONG WINDS WILL FURTHER MAINTAIN NEAR BLIZZARD CONDITIONS. RADAR TRENDS INDICATE AN INCREASING BAND OF SNOW ACROSS WRN SD AS OF 630Z...WHICH IS IN AGREEMENT WITH LATEST RUC/NAM/WRF MODELS INDICATING INCREASING PRECIPITATION RATES THROUGH 12Z ACROSS FAR SERN MT AND WRN SD. STRONG NWLY UPSLOPE FLOW WILL KEEP HEAVIEST PRECIP. RATES FOCUSED ACROSS THE NRN BLACK HILLS. WHILE WINDS WILL BE STRONG...RELATIVELY WARM TEMPERATURES IN THE 30S WILL HELP MITIGATE DRIFTING...ALTHOUGH VISIBILITIES WILL BE REDUCED TO ZERO AT TIMES. ..JEWELL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...UNR...BYZ...GGW... 44690489 45570542 46350565 46820527 46910440 46440356 46180344 45180310 44400308 43940346 43930422 WWWW From Mcd at goshenarc.org Wed Apr 19 07:05:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 03:05:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190703 SWOMCD SPC MCD 190702 TNZ000-VAZ000-NCZ000-KYZ000-190900- MESOSCALE DISCUSSION 0556 NWS STORM PREDICTION CENTER NORMAN OK 0202 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN KY THROUGH NERN TN AND EXTREME SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 190702Z - 190900Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY THIS MORNING. LARGE HAIL WILL BE THE PRIMARY THREAT. AREA IS BEING MONITORED FOR A POSSIBLE WW. A PLUME OF STEEP MID LEVEL LAPSE RATES HAS SPREAD EWD INTO PARTS OF THE TN VALLEY. MEANWHILE...A SWLY LOW LEVEL JET CONTINUES TO ADVECT HIGHER THETA-E AIR NEWD BENEATH THE PLUME OF STEEP LAPSE RATES CONTRIBUTING TO MODERATE ELEVATED INSTABILITY WITH MUCAPE AROUND 1500 J/KG. THE LOW LEVEL JET IS FORECAST TO VEER AND SHIFT EWD THROUGH THE TN VALLEY NEXT FEW HOURS WITH WARM ADVECTION AND ISENTROPIC ASCENT BECOMING MAXIMIZED ACROSS PORTIONS OF NERN TN AND SERN KY ON THE COOL SIDE OF A NW-SE ORIENTED STATIONARY FRONT. LATEST RADAR DATA ALREADY SHOW ELEVATED STORMS INCREASING IN THIS AREA...AND THIS TREND IS EXPECTED TO PERSIST THROUGH THE EARLY MORNING HOURS. IN ADDITION TO STEEP MID LEVEL LAPSE RATES AND MODERATE INSTABILITY...CLOUD LAYER SHEAR IS SUFFICIENT FOR UPDRAFTS TO ROTATE WHICH WILL ENHANCE THE POTENTIAL FOR HAIL WITH THE STRONGER STORMS. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...JKL...LMK... 36408250 35718305 35518412 36348439 37158496 37418391 WWWW From Mcd at goshenarc.org Wed Apr 19 08:46:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 04:46:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190844 SWOMCD SPC MCD 190843 KYZ000-191015- MESOSCALE DISCUSSION 0557 NWS STORM PREDICTION CENTER NORMAN OK 0343 AM CDT WED APR 19 2006 AREAS AFFECTED...SWRN KY...S CNTRL KY THROUGH EXTREME SRN IND CONCERNING...TORNADO WATCH 205... VALID 190843Z - 191015Z LINE OF STRONG TO SEVERE STORMS IS EXPECTED TO CONTINUE EWD NEXT FEW HOURS. BEST THREAT FOR AN ISOLATED TORNADO OR TWO EXISTS ON SRN END OF THE LINE ACROSS SWRN KY. OTHERWISE LARGE HAIL AND ISOLATED DAMAGING WIND ARE LIKELY WITH THE STRONGER STORMS. CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW DOWNSTREAM ACROSS S CNTRL KY. EARLY THIS MORNING A LINE OF SEVERE STORMS PERSISTS FROM EXTREME SRN IND SWD INTO SWRN KY. THE 0-3 KM HODOGRAPHS REMAIN LARGE AND FAVORABLE FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS. HOWEVER...THE LINE IS MOSTLY OUTFLOW DOMINANT WITH THE EXCEPTION OF STORMS ON THE SRN END OF THE LINE. THIS SUGGESTS BEST CHANCE FOR AN ISOLATED TORNADO OR TWO WILL PERSIST WITH SRN END STORMS PRIOR TO BEING UNDERCUT BY THE SURGING OUTFLOW BOUNDARY. ACTIVITY IS MOVING ESEWD AT 35 TO 40 KT AND WILL APPROACH THE ERN EDGE OF WW 205 BY 0915-0930Z. MODERATE INSTABILITY PERSISTS DOWNSTREAM FROM THE LINE AND NEW STORMS MAY CONTINUE TO DEVELOP WITHIN ZONE OF ASCENT AND CONVERGENCE ALONG THE OUTFLOW BOUNDARY NEXT COUPLE HOURS. IF STORMS SHOW SIGNS OF MAINTAINING THEIR INTENSITY...ANOTHER WW MIGHT BE NEEDED E OF WW 205. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...PAH... 36998787 37188757 37478735 37838694 37348623 36658624 36708773 WWWW From Mcd at goshenarc.org Wed Apr 19 11:30:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 07:30:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191128 SWOMCD SPC MCD 191128 NCZ000-VAZ000-TNZ000-KYZ000-191230- MESOSCALE DISCUSSION 0558 NWS STORM PREDICTION CENTER NORMAN OK 0628 AM CDT WED APR 19 2006 AREAS AFFECTED...PORTIONS OF MIDDLE AND NERN TN...SERN KY...SWRN VA AND WRN NC CONCERNING...SEVERE THUNDERSTORM WATCH 206...207... VALID 191128Z - 191230Z OVERALL TREND HAS BEEN FOR STORMS IN WW 206 TO WEAKEN...BUT ISOLATED HAIL REMAINS POSSIBLE WITH THE STRONGER CELLS. A LINE OF STRONG STORMS CONTINUES IN WW 207 FROM S CNTRL KY INTO NRN PORTIONS OF MIDDLE TN. THE THREAT FOR ISOLATED HAIL AND POSSIBLY STRONG WIND GUSTS IS EXPECTED TO PERSIST ANOTHER COUPLE HOURS. SOME OF THIS ACTIVITY WILL SHIFT EWD INTO WRN PORTIONS OF WW 206 THIS MORNING. PORTIONS OF SERN TN WILL BE MONITORED FOR A POSSIBLE WW LATER THIS MORNING. THE LOW LEVEL JET HAS VEERED TO WLY ACROSS TN. WARM ADVECTION AND ISENTROPIC ASCENT CONTINUES TO SUPPORT THUNDERSTORM DEVELOPMENT FROM SERN KY...SWRN VA...NERN TN AND WRN NC. HOWEVER...OVERALL TREND HAS BEEN FOR STORMS TO WEAKEN AS INITIAL STRONG CELLS HAVE MERGED...RESULTING IN A FAIRLY WIDESPREAD STRATIFORM REGION OVER PARTS OF NERN TN INTO WRN NC. SOME OF THE STRONGER CELLS ON THE PERIPHERY OF THE STRATIFORM RAIN AREA MAY STILL BE CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL. OTHER STORMS ARE DEVELOPING FARTHER W FROM S CNTRL KY SWD INTO NRN PARTS OF MIDDLE TN. STORMS ARE EXPECTED TO CONTINUE DEVELOPING ALONG THE GUST FRONT AND ARE BEGINNING TO SPREAD INTO NWRN PORTIONS OF WW 206. STRONGEST STORMS ARE EXPECTED TO PERSIST ON THE SRN END OF THE LINE. THE DECOUPLED BOUNDARY LAYER HAS SO FAR SERVED AS A LIMITING FACTOR FOR WIDESPREAD DAMAGING WIND. HOWEVER...AS HEATING COMMENCES...SOME RE-INTENSIFICATION MAY OCCUR...ESPECIALLY ACROSS PARTS OF SERN TN...AND THIS AREA WILL BE MONITORED FOR A POSSIBLE WW LATER THIS MORNING. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...GSP...MRX...JKL...LMK...OHX... 35278335 35928542 36118612 36748538 37378479 37528315 37028239 35498151 WWWW From Mcd at goshenarc.org Wed Apr 19 13:00:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 09:00:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191258 SWOMCD SPC MCD 191258 GAZ000-NCZ000-TNZ000-191500- MESOSCALE DISCUSSION 0559 NWS STORM PREDICTION CENTER NORMAN OK 0758 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN TN THROUGH NWRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191258Z - 191500Z THUNDERSTORMS MAY INTENSIFY LATER THIS MORNING AS THEY DEVELOP SEWD THROUGH SERN TN AND INTO NWRN GA. DAMAGING WIND AND LARGE HAIL WILL BE THE PRIMARY THREATS. AREA WILL BE MONITORED FOR A POSSIBLE WW WITHIN THE NEXT COUPLE HOURS. EARLY THIS MORNING A SQUALL LINE WAS MOVING SEWD THROUGH ERN TN AT AROUND 35 KT. THE 12Z RAOB FROM ATL SHOWS THE BOUNDARY LAYER TO BE STABLE...BUT WITH MODERATE MUCAPE AND STEEP LAPSE RATES ABOVE THE BOUNDARY LAYER. WIDESPREAD CLOUDS EXIST THIS MORNING ACROSS MUCH OF GA...BUT THESE CLOUDS ARE EXPECTED TO BEGIN TO MIX OUT FROM THE NW ALLOWING THE BOUNDARY LAYER TO DESTABILIZE. STEEP LAPSE RATES UPSTREAM WILL SPREAD EWD ABOVE THE MOIST BOUNDARY LAYER AND CONTRIBUTE TO FURTHER DESTABILIZATION AS SURFACE HEATING COMMENCES. RAOB DATA SUGGEST SURFACE TEMPERATURES IN THE MID 70S ARE NEEDED FOR STORMS TO BECOME SURFACE BASED...AND THIS WILL LIKELY OCCUR AS THE BOUNDARY LAYER CONTINUES TO WARM DOWNSTREAM FROM THE SEWD ADVANCING STORMS. THE LOW LEVEL FLOW IS FORECAST TO GRADUALLY WEAKEN...BUT DEEP LAYER SHEAR PROFILES WILL REMAIN SUFFICIENT FOR ORGANIZED STORM STRUCTURES INCLUDING BOW ECHOES AND SUPERCELLS. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC... 33848478 35068565 35288447 34728415 34028400 WWWW From Mcd at goshenarc.org Wed Apr 19 16:59:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 12:59:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191657 SWOMCD SPC MCD 191656 SCZ000-GAZ000-191900- MESOSCALE DISCUSSION 0560 NWS STORM PREDICTION CENTER NORMAN OK 1156 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN GA/SRN SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191656Z - 191900Z SEVERE THREAT EXPECTED TO SLOWLY INCREASE ACROSS SERN GA OVER THE NEXT FEW HOURS. NEW WW IS ANTICIPATED...THOUGH NOT IMMINENT. LESSER SEVERE THREAT -- MAINLY IN THE FORM OF HAIL -- ALSO EXPECTED WITH MAINLY ELEVATED STORMS ACROSS SRN SC THROUGH THE AFTERNOON. BOUNDARY LAYER IS DESTABILIZING ACROSS SERN GA...AS DAYTIME HEATING CONTINUES PER LATEST SURFACE OBS/VISIBLE SATELLITE IMAGERY SOUTHWEST OF NW-SE OUTFLOW BOUNDARY GENERATED BY ONGOING CONVECTION OVER NRN AND ERN GA/SC. THIS BOUNDARY CURRENTLY EXTENDS FROM NWRN GA SEWD ACROSS CENTRAL GA TO NEAR SAV...SW OF WHICH INSTABILITY HAS INCREASED TO AROUND 500 J/KG MEAN-LAYER CAPE. THOUGH VARIOUS MODEL SOUNDINGS REVEAL CAPPED BOUNDARY LAYER EARLY THIS AFTERNOON -- CONFIRMED BY GRAVITY WAVE APPARENT IN VISIBLE LOOP...CONTINUED HEATING/MIXING COMBINED WITH LIFT INVOF OUTFLOW BOUNDARY SHOULD PROVE SUFFICIENT FOR CONVECTIVE DEVELOPMENT. WITH LOW-LEVEL FLOW VEERING/INCREASING TO NWLY AT 40 TO 45 KT AT MID LEVELS...THREAT FOR ORGANIZED SEVERE STORMS EXISTS. THOUGH SUPERCELLS WILL BE POSSIBLE...IT APPEARS MOST LIKELY THAT STORMS SHOULD ORGANIZED INTO A SEWD-MOVING LINE/BOW WITH TIME...CAPABLE OF DAMAGING WINDS AND HAIL. FURTHER NW -- ON COOL SIDE OF OUTFLOW BOUNDARY ACROSS SC...STRONG/LOCALLY SEVERE STORMS SHOULD CONTINUE MOVING SEWD ACROSS THIS REGION. THOUGH LOCAL HEATING MAY ALLOW SUFFICIENT SURFACE-BASED DESTABILIZATION FOR LIMITED DAMAGING WIND POTENTIAL...HAIL SHOULD REMAIN THE MORE LIKELY SEVERE THREAT. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...CAE...JAX...FFC...TAE... 33488348 33698236 33748153 32738008 30978152 30688369 32098418 33048418 WWWW From Mcd at goshenarc.org Wed Apr 19 17:37:36 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 13:37:36 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191735 SWOMCD SPC MCD 191735 MSZ000-LAZ000-ARZ000-TXZ000-191930- MESOSCALE DISCUSSION 0561 NWS STORM PREDICTION CENTER NORMAN OK 1235 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN TX...FAR SRN AR AND NRN LA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191735Z - 191930Z ISOLATED SVR STORMS /WITH LARGE HAIL THE PRIMARY THREAT/ MAY DEVELOP BY 19Z OVER THE ARKLATEX AREA EWD ALONG THE AR/LA BORDER. AREA CONTINUES TO BE MONITORED FOR A POSSIBLE WW. 17Z SURFACE MESOANALYSIS PLACES A MESOLOW OVER FAR NERN TX NEAR GGG...WITH A STATIONARY FRONT EXTENDING EWD FROM THE LOW ALONG THE AR/LA BORDER. MODIFIED 12Z SHV SOUNDING FOR 17Z SFC CONDITIONS INDICATES LESS THAN 50 J/KG OF MLCINH REMAINS WITH MODERATE CU OBSERVED RECENTLY ON VIS SAT IMAGERY JUST EAST OF GGG. ENHANCED CONVERGENCE IN THE VICINITY OF THE MESOLOW AND CONTINUED BOUNDARY LAYER HEATING/DIMINISHING CINH MAY BE ENOUGH SUPPORT FOR ISOLATED CONVECTIVE DEVELOPMENT IN THE NEXT 2 HRS. DESPITE MARGINAL EFFECTIVE LAYER SHEAR FOR ORGANIZED STORM ROTATION /35-40 KTS PER RECENT DE QUEEN AND PALESTINE PROFILER DATA /...MODERATE TO STRONG INSTABILITY /MLCAPES AROUND 2500 J/KG / WILL AID IN STRONG UPDRAFT INTENSITY AND POTENTIAL FOR LARGE HAIL. IN ADDITION...MID LEVEL THERMAL TROUGH /EVIDENT PER ACCAS FIELD ON SAT DATA/ SUGGESTS STEEP MID LEVEL LAPSE RATES /AROUND 8 DEG C/KM / FURTHER SUPPORTING THREAT FOR LARGE SVR HAIL. ALONG WITH THE POTENTIAL FOR SURFACE INITIATED SVR CONVECTION ALONG THE STATIONARY BOUNDARY...SOME OF THIS ACCAS MAY EVENTUALLY BECOME ROOTED IN THE BOUNDARY LAYER /AND BECOME SVR/ AS IT MOVES ENEWD ACROSS NRN LA THIS AFTERNOON. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV... 33419209 33299303 33209380 33139417 32779466 32449490 31959488 31659435 31609364 31779186 32349099 33199132 WWWW From Mcd at goshenarc.org Wed Apr 19 18:42:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 14:42:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191840 SWOMCD SPC MCD 191839 GAZ000-ALZ000-192015- MESOSCALE DISCUSSION 0562 NWS STORM PREDICTION CENTER NORMAN OK 0139 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN AL/NWRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 208... VALID 191839Z - 192015Z STRONG/SEVERE STORMS CONTINUE -- MOST OF WHICH REMAIN SLIGHTLY ELEVATED ON THE COOL SIDE OF SWWD-MOVING OUTFLOW BOUNDARY WHERE WARM ADVECTION ASSOCIATED WITH WLY LOW-LEVEL JET IS MAXIMIZED. STEEP LAPSE RATES JUST OFF THE SURFACE CONTINUE TO SUPPORT MODERATE TO STRONG INSTABILITY...REFLECTED BY OBJECTIVELY-ANALYZED 3500 TO 4000 J/KG MEAN-LAYER CAPE ACROSS NERN MS/NWRN AL -- W OF OUTFLOW WITHIN WARM SECTOR. THOUGH SOME POTENTIAL REMAINS FOR STORMS TO DEVELOP NEAR -- AND THEN ORGANIZE AND RIDE SEWD ALONG -- SURFACE OUTFLOW BOUNDARY...IN WHICH CASE THREAT FOR DAMAGING WINDS WOULD INCREASE...IT APPEARS THAT MAIN SEVERE THREAT MAY REMAIN HAIL WITH SLIGHTLY-ELEVATED STORMS ON COOL SIDE OF OUTFLOW. WITH OUTFLOW BOUNDARY -- AND ASSOCIATED STORM DEVELOPMENT -- CONTINUING TO PROGRESS SWWD TOWARD WRN PORTIONS OF WW OVER AL...THREAT MAY SPILL JUST W OF CURRENT WW AREA WITH TIME. HOWEVER...OVERALL WWD EXTENT OF THREAT SHOULD BE LIMITED BY APPARENT PRE-FRONTAL TROUGH/CONVERGENCE AXIS MOVING SLOWLY EWD ACROSS NWRN AL. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN... 34958591 34268384 33008303 32378555 32918768 34938746 WWWW From Mcd at goshenarc.org Wed Apr 19 19:33:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 15:33:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191931 SWOMCD SPC MCD 191931 GAZ000-ALZ000-192100- MESOSCALE DISCUSSION 0564 NWS STORM PREDICTION CENTER NORMAN OK 0231 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN AND ERN AL/W CENTRAL GA CONCERNING...SEVERE THUNDERSTORM WATCH 208... VALID 191931Z - 192100Z THUNDERSTORMS CONTINUE TO DEVELOP WWD ACROSS GA INTO AL. NEW WW WILL LIKELY BE REQUIRED...TO REPLACE WW 208 WHICH IS SCHEDULED TO EXPIRE AT 20/21Z. LATEST RADAR IMAGERY CONTINUES TO SHOW SLIGHTLY-ELEVATED THUNDERSTORMS -- NOW SHOWING SUPERCELL CHARACTERISTICS -- DEVELOPING WWD ACROSS NWRN AL JUST TO THE COOL SIDE OF WSWWD-MOVING OUTFLOW BOUNDARY. ADDITIONALLY... A NEW STORM HAS DEVELOPED OVER SRN MORGAN COUNTY AL...NEAR THE INTERSECTION OF THE NW-SE OUTFLOW BOUNDARY AND NW-SW PRE-FRONTAL TROUGH. WITH WEAK SHORT-WAVE RIDGING ACROSS THIS AREA...IT APPEARS THAT STORM DEVELOPMENT WILL REMAIN LIMITED TO ZONES OF LOW-LEVEL FORCING INVOF SURFACE BOUNDARIES. THUS...EXPECT SUBSEQUENT DEVELOPMENT OF STORMS TO REMAIN TIED TO THE OUTFLOW...AND INVOF THE OUTFLOW/SURFACE TROUGH INTERSECTION. GIVEN STRONG INSTABILITY AND FAVORABLE SHEAR...CONTINUED THREAT FOR SEVERE/SUPERCELL STORMS SHOULD PERSIST INTO THE EVENING...WELL BEYOND THE 21Z EXPIRATION OF WW 208. THEREFORE...NEW WW WILL LIKELY BE ISSUED SHORTLY...ADDRESSING THE ONGOING THREAT FOR HAIL AND THE POTENTIAL FOR LOCALLY DAMAGING WINDS AND/OR A COUPLE TORNADOES. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...HUN... 34708535 33258393 32248338 31698536 32888728 34938746 WWWW From Mcd at goshenarc.org Wed Apr 19 20:21:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:21:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192019 SWOMCD SPC MCD 192018 TXZ000-192215- MESOSCALE DISCUSSION 0565 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT WED APR 19 2006 AREAS AFFECTED...CENTRAL/NCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192018Z - 192215Z ISOLATED SVR HAIL MAY BE POSSIBLE WITH DEVELOPING ELEVATED CONVECTION AS IT MOVES FROM SWRN INTO CENTRAL/NCENTRAL TX THROUGH THE REST OF THE AFTERNOON. ATTM A WW IS NOT ANTICIPATED BUT TRENDS WILL CONTINUE TO BE MONITORED. REGIONAL VWP DATA INDICATES THAT THE STRONGEST WARM ADVECTION WAS LOCATED IN THE 1-2 KM LAYER. IN THIS LAYER...MOISTURE WAS INCREASING BENEATH A CAPPING INVERSION CENTERED AROUND 3 KM. SUFFICIENT MOISTENING/ASCENT HAS DEVELOPED OVER THE LAST 1-2 HRS TO INITIATE A FEW ELEVATED SHOWERS/TSTMS OVER SWRN TX 50-75 MILES NORTH OF THE SFC FRONTAL BOUNDARY. INSPECTION OF RECENT RUC/NAM FORECAST SOUNDINGS INDICATE AROUND 1500-2000 J/KG OF ELEVATED MUCAPE IS POSSIBLE IF THE MID LEVEL CAPPING INVERSION IS NEGATED. GIVEN THE RELATIVELY WEAK ISENTROPIC ASCENT EXPECTED THROUGH 00Z...IT IS UNCERTAIN IF THE COVERAGE AND/OR INTENSITY OF THIS CONVECTION THAT RECENTLY DEVELOPED WILL INCREASE. HOWEVER...IF CONVECTION BEGINS TO INCREASE IN INTENSITY...FAVORABLE THERMODYNAMIC PARAMETERS COMBINED WITH 40-50 KTS OF EFFECTIVE SHEAR BE SUPPORTIVE OF A THREAT FOR SVR HAIL NEWD INTO NCENTRAL TX. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...SJT... 33219708 31750007 30930076 30670058 30789931 31689762 32339650 33139607 33309639 WWWW From Mcd at goshenarc.org Wed Apr 19 20:43:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:43:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192040 SWOMCD SPC MCD 192040 GAZ000-FLZ000-ALZ000-192245- MESOSCALE DISCUSSION 0566 NWS STORM PREDICTION CENTER NORMAN OK 0340 PM CDT WED APR 19 2006 AREAS AFFECTED...SRN GA/SERN AL/NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192040Z - 192245Z SEVERE THREAT INCREASING ALONG OUTFLOW BOUNDARY ACROSS SERN AL/SRN GA. NEW WW MAY BE REQUIRED. MOIST/UNSTABLE AIRMASS /MEAN-LAYER CAPE 1000 TO 1500 J/KG/ IS INDICATED NEAR AND S OF MAIN OUTFLOW BOUNDARY...WHICH CURRENTLY EXTENDS FROM LEE COUNTY AL ESEWD ACROSS SRN GA TO COASTAL AREAS OF CHATHAM/LIBERTY/BRYAN COUNTIES IN SERN GA. CONVECTIVE TOWERS ARE EVIDENT ALONG THIS BOUNDARY...ALONG WITH A FEW THUNDERSTORMS OVER COASTAL SE GA...NEAR INTERSECTION OF THE BOUNDARY WITH A WWD-MOVING SEA-BREEZE BOUNDARY. THOUGH INSTABILITY AND SHEAR ARE SOMEWHAT MORE LIMITED ACROSS THIS REGION AS OPPOSED TO AREAS FURTHER N...PARAMETERS ARE NONETHELESS SUPPORTIVE OF SEVERE THREAT. THOUGH CAPPING HAS HELD CONVECTION IN CHECK THUS FAR...EXPECT AN INCREASE IN STORMS OVER THE NEXT COUPLE OF HOURS THROUGH PEAK DIURNAL HEATING PERIOD. WITH THREAT FOR HAIL AND DAMAGING WINDS LIKELY TO ACCOMPANY ANY VIGOROUS UPDRAFTS WHICH DEVELOP...NEW WW MAY BE REQUIRED. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...JAX...FFC...TAE...BMX... 31818127 31178146 30398153 30248246 30558451 31318549 32208608 32258545 31778348 WWWW From Mcd at goshenarc.org Wed Apr 19 20:52:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:52:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192050 SWOMCD SPC MCD 192050 MSZ000-ARZ000-LAZ000-TXZ000-192245- MESOSCALE DISCUSSION 0567 NWS STORM PREDICTION CENTER NORMAN OK 0350 PM CDT WED APR 19 2006 AREAS AFFECTED...FAR SRN AR...ECENTRAL/NERN TX AND NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 192050Z - 192245Z CONTINUE ALL OF WW 209. ELEVATED CONVECTION HAS YET TO BECOME ROOTED IN THE BOUNDARY LAYER AND STRENGTHEN. SINCE IT/S STILL RELATIVELY EARLY IN THE AFTERNOON...THERE REMAINS SOME POTENTIAL FOR THIS CONVECTION TO STILL BECOME ROOTED AND INTENSIFY AS CINH REMAINS RELATIVELY LOW OVER NRN LA/ECENTRAL TX. ALSO...RECENT SAT IMAGERY SHOWS THAT CINH REMAINS WEAK OVER NRN PORTIONS OF WW 209 AS TOWERING CU IS EVIDENT OVER FAR NERN TX /IN THE VICINITY OF A MESOLOW/ AND TO A LESSER EXTENT ALONG THE STATIONARY BOUNDARY ACROSS FAR SRN AR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33409302 33619414 33379475 32669539 31419540 31039532 31969102 33769120 WWWW From Mcd at goshenarc.org Wed Apr 19 20:58:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:58:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192055 SWOMCD SPC MCD 192055 MSZ000-ARZ000-LAZ000-TXZ000-192300- MESOSCALE DISCUSSION 0567 NWS STORM PREDICTION CENTER NORMAN OK 0355 PM CDT WED APR 19 2006 AREAS AFFECTED...FAR SRN AR...ECENTRAL/NERN TX AND NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 192055Z - 192300Z CONTINUE ALL OF WW 209. ELEVATED CONVECTION HAS YET TO BECOME ROOTED IN THE BOUNDARY LAYER AND STRENGTHEN. SINCE IT/S STILL RELATIVELY EARLY IN THE AFTERNOON...THERE REMAINS SOME POTENTIAL FOR THIS CONVECTION TO STILL BECOME ROOTED AND INTENSIFY AS CINH REMAINS RELATIVELY LOW OVER NRN LA/ECENTRAL TX. ALSO...RECENT SAT IMAGERY SHOWS THAT CINH REMAINS WEAK OVER NRN PORTIONS OF WW 209 AS TOWERING CU IS EVIDENT OVER FAR NERN TX /IN THE VICINITY OF A MESOLOW/ AND TO A LESSER EXTENT ALONG THE STATIONARY BOUNDARY ACROSS FAR SRN AR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33409302 33619414 33379475 32669539 31419540 31039532 31969102 33769120 WWWW From Mcd at goshenarc.org Wed Apr 19 21:52:38 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 17:52:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192150 SWOMCD SPC MCD 192150 ALZ000-MSZ000-192315- MESOSCALE DISCUSSION 0568 NWS STORM PREDICTION CENTER NORMAN OK 0450 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN CNTRL MS...WRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192150Z - 192315Z SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER THE NEXT 1-2 HOURS ACROSS NRN MS WITH CONVECTION EXPANDING IN COVERAGE AND DRIFTING SSEWD ACROSS ERN MS AND WRN AL. A WW WILL LIKELY BE NEEDED BY 2230Z ACROSS THE REGION. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT MOVING SSEWD ACROSS NRN MS WITH DEWPOINTS NEAR 70 F JUST SOUTH OF THE BOUNDARY. THE HIGH SFC DEWPOINTS AND TEMPERATURES NEAR 90 F ARE RESULTING IN STRONG INSTABILITY. THIS COMBINED WITH A WEAKENING CAPPING INVERSION WILL ALLOW STORMS TO INITIATE AND SPREAD SSEWD THIS EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW MID-LEVEL WINDS OF 30 KT...SUBSTANTIAL DIRECTIONAL SHEAR EXISTS BELOW 700 MB WHICH SHOULD BE SUFFICIENT FOR SUPERCELL DEVELOPMENT. STEEP MID-LEVEL LAPSE RATES NEAR 8.0 C/KM WILL BE FAVORABLE FOR LARGE HAIL. IN ADDITION...TEMP-DEWPOINT SPREADS OF GREATER THAN 20 DEGREES F WILL ENHANCE THE WIND DAMAGE POTENTIAL WITH THE STRONGER SUPERCELLS AND MORE WELL-DEVELOPED LINE SEGMENTS. ..BROYLES.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MOB...MEG...JAN... 34119007 34468917 34418843 33718741 33038711 32448701 32188780 32118867 32428940 32959020 33489031 33689029 WWWW From Mcd at goshenarc.org Wed Apr 19 22:14:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 18:14:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192212 SWOMCD SPC MCD 192212 TXZ000-200015- MESOSCALE DISCUSSION 0569 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT WED APR 19 2006 AREAS AFFECTED...NCENTRAL/NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192212Z - 200015Z ISOLATED STORMS OVER CENTRAL TX /SW OF THE DFW METRO AREA/ MAY INTENSIFY AND BECOME SVR AS THEY MOVE ENEWD ACROSS NCENTRAL/NERN TX /AND INTO WRN PORTIONS OF WW 209/ OVER THE NEXT FEW HRS. LARGE HAIL SHOULD BE THE PRIMARY THREAT. WE ARE CONTINUING TO MONITOR TRENDS FOR A POSSIBLE WW. RECENT SAT OBS INDICATES THAT ELEVATED MOISTURE /CENTERED AROUND THE 850 MB LAYER/ WAS BEGINNING TO ADVANCE MORE RAPIDLY NORTH OF A SFC FRONTAL BOUNDARY THAT HAS BEGUN TO RETREAT NWD OVER CENTRAL TX. AS THIS MOISTURE MOVES NWD...IT SHOULD BEGIN TO ERODE THE MID LEVEL CAPPING INVERSION CENTERED AROUND 3 KM AND AID IN AN INTENSIFICATION PROCESS WITH THE CLUSTER OF STORMS MOVING OUT OF SWRN TX. FCST SOUNDINGS INDICATE THAT GIVEN THIS SCENARIO AROUND 2000 J/KG OF MUCAPE WILL BE REALIZED BY THESE STORMS OVER NCENTRAL/NERN TX. GIVEN 40-45 KTS OF CLOUD BEARING SHEAR...AN INCREASING SVR HAIL THREAT WOULD THUS OCCUR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...FWD... 33249467 32769717 32569790 32359873 32129881 31499838 31469761 31609668 32119513 32329445 32959425 WWWW From Mcd at goshenarc.org Wed Apr 19 22:55:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 18:55:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192253 SWOMCD SPC MCD 192253 TXZ000-200100- MESOSCALE DISCUSSION 0570 NWS STORM PREDICTION CENTER NORMAN OK 0553 PM CDT WED APR 19 2006 AREAS AFFECTED...SWRN/CENTRAL TX CONCERNING...SEVERE THUNDERSTORM WATCH 211... VALID 192253Z - 200100Z THREAT FOR SVR STORMS WILL LIKELY REMAIN LOW FOR MOST OF WW 211 FOR THE NEXT 1-2 HRS /THROUGH 00Z/. HOWEVER THE SVR THREAT IS ANTICIPATED TO INCREASE / ESPECIALLY OVER WRN/NRN PORTIONS OF WW 211 THEREAFTER/. A LARGE CIRRUS CANOPY ASSOCIATED WITH SVR TSTM CLUSTER OVER NRN COAHUILA MX HAS STABILIZED MUCH OF THE MIDDLE RIO GRANDE VALLEY EWD INTO THE EDWARDS PLATEAU REGION. THIS IS EVIDENT BY A 5-7 DEG COOLING TREND NOTED IN RECENT SFC OBS FROM DRT AND ECU. CONVECTION ON THE NRN EXTENSION OF THE HIGHER TERRAIN OF NRN COAHUILA /AND NORTH OF THE LARGE CIRRUS SHIELD/ MAY BE THE FIRST TO POSE A RENEWED SVR THREAT AS IT MOVES INTO NRN VAL VERDE...CROCKETT AND SUTTON COUNTIES IN THE NEXT FEW HRS. A GREATER SVR THREAT IS ANTICIPATED WITH SUPERCELL THUNDERSTORMS NOW MOVING INTO THE LOWER ELEVATIONS OF NRN COAHUILA MX AS THEY MAINTAIN THEMSELVES AND MOVE INTO SRN MAVERICK COUNTY /AROUND 01Z/. FURTHER NORTH...ELEVATED SVR POTENTIAL WILL LIKELY INCREASE AFTER 00Z OVER THE NRN EDWARDS PLATEAU/CONCHO VALLEY REGION AS ISENTROPIC LIFT STRENGTHENS NORTH OF A SLOWLY MOVING WARM FRONT. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT... 31520019 30780115 29920121 28510116 29739801 31909807 WWWW From Mcd at goshenarc.org Thu Apr 20 00:33:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:33:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200031 SWOMCD SPC MCD 200031 TXZ000-200230- MESOSCALE DISCUSSION 0571 NWS STORM PREDICTION CENTER NORMAN OK 0731 PM CDT WED APR 19 2006 AREAS AFFECTED...LOWER-MIDDLE RIO GRANDE RIVER VALLEY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200031Z - 200230Z CLUSTER OF SVR STORMS OVER NERN COAHUILA MX WILL CONTINUE TO MOVE EWD AROUND 20-25 KTS AND ENTER WEBB AND DIMMIT COUNTIES AROUND 02Z. THREAT FOR LARGE HAIL AND DMGG WINDS APPEAR LIKELY IF STORMS CAN MAINTAIN INTENSITY BEFORE ENCOUNTERING STRONGER INHIBITION FURTHER EAST. 00Z DRT/BRO SOUNDINGS INPUT WITH OBSERVATION AT LRD INDICATES A EXTREMELY UNSTABLE AIRMASS WITH MLCAPES IN EXCESS OF 4000 J/KG. CLUSTER OF SVR STORMS /WITH SUPERCELL STRUCTURE/ OVER NERN COAHUILA MX WILL MOVE EWD AND SHOULD CROSS THE RIO GRANDE AROUND 02Z. GIVEN THE AIRMASS IN PLACE OVER THE MIDDLE-LOWER RIO GRANGE RIVER VALLEY..IT IS ANTICIPATED THAT A SVR THREAT WILL CONTINUE INTO THIS AREA. HOWEVER...FURTHER EAST...CINH WAS HIGHER AND SHOULD CONTINUE TO INCREASE WITH BOUNDARY LAYER COOLING THIS EVENING. THUS THE SVR THREAT IS NOT ANTICIPATED TO BE MUCH GREATER THAN A 3-5 COUNTY AREA SOUTH OF WW 211. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CRP...EWX...BRO... 29079962 28700010 27779989 27219925 27559888 28079875 29209910 WWWW From Mcd at goshenarc.org Thu Apr 20 00:44:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:44:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200041 SWOMCD SPC MCD 200041 MSZ000-ARZ000-LAZ000-TXZ000-200215- MESOSCALE DISCUSSION 0572 NWS STORM PREDICTION CENTER NORMAN OK 0741 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN/ECENTRAL TX...NRN LA AND SRN AR CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 200041Z - 200215Z THREAT FOR SVR APPEARS TO BE LOW FOR THE REMAINDER OF WW 209 VALID TIME /02Z/. HOWEVER...GIVEN THE LOW PROBABILITY THAT STILL REMAINS AND MODERATE INSTABILITY NO CLEARANCE OF WW 209 APPEARS WARRANTED ATTM. 00Z SHV SOUNDING SHOWED A NEARLY UNCAPPED MODERATELY UNSTABLE PROFILE WITH MLCAPES AROUND 2500 J/KG. THE PASSAGE OF A WEAK SHORTWAVE AND ELEVATED CONVECTION HAS NOW LEFT MOST OF WW 209 IN A REGION OF NEUTRAL FORCING. ALONG WITH THIS...THE SYNOPTIC BOUNDARY THAT WAS ONCE ALONG THE AR/LA BORDER HAS GRADUALLY LIFTED NWD AND IS NOW ALONG THE FAR NRN EDGE OF WW 209 ACROSS SRN AR. GIVEN LIMITED REMAINING HEATING AND WEAK CONVERGENCE ALONG THIS BOUNDARY NEW TSTM DEVELOPMENT APPEARS UNLIKELY TO OCCUR. FURTHER WEST...ELEVATED CONVECTION /REF 00Z FWD SOUNDING/ IN A MODERATELY UNSTABLE ENVIRONMENT /MUCAPES AROUND 2000 J/KG/ WILL LIKELY NOT MOVE INTO WW 209 UNTIL AFTER 02Z GIVEN RECENT OBSERVED CELL MOTIONS. HOWEVER GIVEN THE DEGREE OF INSTABILITY AND LIMITED CINH IN PLACE...IT IS POSSIBLE THAT THIS NCENTRAL TX CONVECTIVE ACTIVITY MAY STILL INTENSIFY AS IT MOVES EWD AND THUS A NEW WW MAY BE NEEDED FOR PORTIONS OF THE AREA AFTER 02Z. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33329472 32669545 30989538 31979116 33699119 33559374 WWWW From Mcd at goshenarc.org Thu Apr 20 00:53:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:53:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200051 SWOMCD SPC MCD 200051 GAZ000-FLZ000-ALZ000-200215- MESOSCALE DISCUSSION 0573 NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT WED APR 19 2006 AREAS AFFECTED...AL...SW GA...NRN FL CONCERNING...TORNADO WATCH 210... VALID 200051Z - 200215Z A SEVERE THREAT WILL LIKELY CONTINUE ACROSS PARTS OF AL...SW GA AND NRN FL THROUGH MUCH OF THE EVENING. THE THREAT IN AL SHOULD GRADUALLY SHIFT SWWD ACROSS THE SE PART OF WW 213. ALTHOUGH THE AREA ACROSS ERN AL AND WRN GA WILL CONTINUE TO BE MONITORED...IT APPEARS A NEW WATCH WILL NOT BE NECESSARY TO REPLACE WW 210. A LARGE COMPLEX OF MOSTLY ELEVATED STORMS IS CURRENTLY ONGOING IN NCNTRL AL JUST BEHIND THE COOL SIDE OF A FRONTAL BOUNDARY. THE FRONTAL BOUNDARY AIDED BY THUNDERSTORM OUTFLOW IS MOVING WWD EVIDENT ON WSR-88D. AS THE BOUNDARY MOVES INTO CNTRL AL...NEW CONVECTIVE DEVELOPMENT SHOULD OCCUR WITH THE ONGOING MCS DRIFTING SLOWLY SSWWD ACROSS THE SERN PART OF WW 213. FORECAST SOUNDINGS SUGGEST THE INSTABILITY AND SHEAR ENVIRONMENT WILL CONTINUE TO REMAIN SUPPORTIVE OF SEVERE STORMS ALTHOUGH A GRADUAL DECREASE IN THE SEVERE WEATHER COVERAGE ACROSS CNTRL AL AND SWRN GA/NRN FL WILL LIKELY OCCUR AS INSTABILITY SLOWLY DECREASES THIS EVENING. ..BROYLES.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...HUN...MOB... 30878551 31908695 32838792 33318798 33848766 33928695 33618652 32928587 31658411 31298391 31008396 30598436 30618489 WWWW From Mcd at goshenarc.org Thu Apr 20 01:32:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 21:32:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200130 SWOMCD SPC MCD 200130 TXZ000-200230- MESOSCALE DISCUSSION 0574 NWS STORM PREDICTION CENTER NORMAN OK 0830 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200130Z - 200230Z SEVERE STORMS WITH LARGE HAIL ARE EXPECTED TO INCREASE IN COVERAGE THROUGH THE EVENING. A WW MAY BE REQUIRED. STORMS CONTINUE TO INCREASE N OF WARM FRONT IN WARM ADVECTION ZONE. VERY STEEP LAPSE RATES ARE IN PLACE WITH STRONG ELEVATED INSTABILITY. IN ADDITION...EFFECTIVE DEEP LAYER SHEAR VECTORS ARE FAVORABLE FOR ORGANIZED SEVERE CONVECTION. GIVEN CONTINUING WARM ADVECTION...STORMS WILL LIKELY PERSIST FOR SEVERAL HOURS. ..JEWELL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 31840189 32850151 33270041 33489746 33309648 32049607 31479672 31669983 31470161 WWWW From Mcd at goshenarc.org Thu Apr 20 07:46:23 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 03:46:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200744 SWOMCD SPC MCD 200743 TXZ000-200845- MESOSCALE DISCUSSION 0575 NWS STORM PREDICTION CENTER NORMAN OK 0243 AM CDT THU APR 20 2006 AREAS AFFECTED...W CNTRL THROUGH PARTS OF WRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 214... VALID 200743Z - 200845Z SEVERE THUNDERSTORM WATCH 214 WILL PROBABLY NEED TO BE REPLACED BY ANOTHER WW BY 08Z. STORMS ARE EXPECTED TO CONTINUE AND MAY DEVELOP FARTHER W LATER THIS MORNING. PRIMARY THREATS WILL BE LARGE HAIL. EARLY THIS MORNING...A SELY LOW LEVEL JET AROUND 30 KT WILL PERSIST ACROSS S CNTRL THROUGH WRN TX. THIS WILL CONTINUE TO ADVECT HIGHER THETA-E AIR NWWD WITH TIME BENEATH STEEP MID LEVEL LAPSE RATES. STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE OF LIFT WHERE THE LOW LEVEL JET IS INTERSECTING THE OUTFLOW BOUNDARY. WV IMAGERY SHOWS A SHORTWAVE TROUGH MOVING EWD THROUGH NM. DEEP LAYER ASCENT ASSOCIATED WITH THIS FEATURE AND LIFT ASSOCIATED WITH THE SELY LOW LEVEL JET MAY CONTRIBUTE TO THUNDERSTORM DEVELOPMENT LATER THIS MORNING AS THE ATMOSPHERE DESTABILIZES FARTHER W. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...SJT...MAF... 32349831 31950077 31760231 32440247 32920175 32860005 32769831 WWWW From Mcd at goshenarc.org Thu Apr 20 09:24:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 05:24:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200922 SWOMCD SPC MCD 200922 TNZ000-KYZ000-ILZ000-MOZ000-ARZ000-201115- MESOSCALE DISCUSSION 0576 NWS STORM PREDICTION CENTER NORMAN OK 0422 AM CDT THU APR 20 2006 AREAS AFFECTED...EXTREME NERN AR THROUGH WRN TN...NRN PARTS OF MIDDLE TN AND SWRN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200922Z - 201115Z THREAT FOR PRIMARILY ISOLATED HAIL WILL EXIST WITH STRONGER STORMS DEVELOPING OVER PARTS OF WRN TN AND SWRN KY. AREA WILL CONTINUE TO BE MONITORED. STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE OF WEAK WARM ADVECTION ALONG A MODEST 20 TO 25 KT LOW LEVEL JET FROM WRN THROUGH MIDDLE TN AND INTO WRN AND CNTRL KY. THE ATMOSPHERE IN THIS REGION IS MODERATELY UNSTABLE WITH MID LEVEL 700 TO 500 MB LAPSE RATES FROM 7.5C TO 8C. VWP DATA SHOW EFFECTIVE VERTICAL SHEAR ONLY MARGINALLY SUPPORTIVE OF ORGANIZED SUSTAINED STORM STRUCTURES...AND DOMINANT STORM TYPE WILL MOST LIKELY BE MULTICELLS. HOWEVER...THE THERMODYNAMIC ENVIRONMENT APPEARS SUPPORTIVE OF HAIL WITH THE STRONGER STORMS. OTHER STORMS OVER NERN AR APPEAR TO HAVE DEVELOPED A COLD POOL AND ARE FORWARD PROPAGATING. STRONG WIND GUSTS AS WELL AS HAIL MAY ACCOMPANY THIS ACTIVITY AS IT MOVES TOWARD WRN TN. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...PAH...MEG... 36118578 35308891 35158992 36078988 37458817 37608571 WWWW From Mcd at goshenarc.org Thu Apr 20 09:57:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 05:57:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200955 SWOMCD SPC MCD 200955 TXZ000-201100- MESOSCALE DISCUSSION 0577 NWS STORM PREDICTION CENTER NORMAN OK 0455 AM CDT THU APR 20 2006 AREAS AFFECTED...SWRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 217... VALID 200955Z - 201100Z LONE STORM REMAINS OVER SWRN TX JUST S OF DEL RIO. THIS STORM MAY STILL BE CAPABLE OF PRODUCING HAIL. HOWEVER...IT IS EXPECTED TO GRADUALLY DIMINISH...AND ADDITIONAL DEVELOPMENT IS NOT ANTICIPATED. WW 217 SHOULD BE ABLE TO BE CANCELLED ONCE THIS STORM DISSIPATES. STORMS THAT DEVELOPED OVER THE HIGHER TERRAIN OF MEXICO HAVE MOSTLY DISSIPATED AS THEY CROSSED INTO SWRN TX...MOST LIKELY AS A RESULT OF ENCOUNTERING STRONGER CONVECTIVE INHIBITION. THE OBSERVED 00Z RAOB FROM DEL RIO AND FORECAST RUC SOUNDING DATA SHOW AN INVERSION ASSOCIATED WITH THE EML IN THE 850 MB TO 700 MB LAYER...AND ADDITIONAL DEVELOPMENT IS NOT ANTICIPATED THROUGH THE EARLY MORNING. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 30139975 28369965 28450116 30000109 WWWW From Mcd at goshenarc.org Thu Apr 20 11:10:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 07:10:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201106 SWOMCD SPC MCD 201106 ARZ000-201300- MESOSCALE DISCUSSION 0578 NWS STORM PREDICTION CENTER NORMAN OK 0606 AM CDT THU APR 20 2006 AREAS AFFECTED...CNTRL AND SRN AR THROUGH NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 216... VALID 201106Z - 201300Z THREAT FOR ISOLATED HAIL EXPECTED TO PERSIST MAINLY ACROSS PARTS OF CNTRL AR NEXT COUPLE HOURS. SKELETAL OUTFLOW BOUNDARY IS SHIFTING SEWD THROUGH NRN LA AND LATEST OBJECTIVE ANALYSIS SHOWS STRONGER CAP IN THIS REGION...WHICH SHOULD CONTINUE TO LIMIT DEVELOPMENT ALONG THIS PORTION OF THE BOUNDARY. FARTHER N...ELEVATED STORMS ARE INCREASING IN COVERAGE WITHIN ZONE OF ASCENT DOWNSTREAM FROM MCV THAT IS MOVING THROUGH NERN TX AND SWRN AR. THE ATMOSPHERE IN THIS REGION REMAINS MODERATELY UNSTABLE WITH STEEP MID LEVEL LAPSE RATES AND SHOULD CONTINUE TO SUPPORT A THREAT FOR HAIL AS STORMS DEVELOP NEXT 2-3 HOURS. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV... 33829137 33769324 34999336 35209161 WWWW From Mcd at goshenarc.org Thu Apr 20 15:18:22 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 11:18:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201516 SWOMCD SPC MCD 201515 TXZ000-201615- MESOSCALE DISCUSSION 0579 NWS STORM PREDICTION CENTER NORMAN OK 1015 AM CDT THU APR 20 2006 AREAS AFFECTED...W TX CONCERNING...SEVERE THUNDERSTORM WATCH 218...219... VALID 201515Z - 201615Z CONTINUE WW 219. PARTS OF WW 218 MAY BE EXTENDED LOCALLY ANOTHER COUPLE OF HOURS. MAIN UPSTREAM SOUTHERN BRANCH IMPULSE IS JUST NOW PROGRESSING INTO THE SOUTHERN ROCKIES...AND ZONE OF STRONGER ISENTROPIC ASCENT IS EXPECTED TO PERSIST FROM AREAS EAST OF THE TEXAS BIG BEND INTO WEST CENTRAL TEXAS INTO EARLY AFTERNOON. THIS EXTENDS FROM JUST NORTH OF STALLED SURFACE FRONT...NEAR/SOUTH OF THE DEL RIO/SAN ANTONIO AREAS ...INTO THE VICINITY OF STRONGER MID-LEVEL BAROCLINIC ZONE ACROSS NORTH CENTRAL TEXAS. THOUGH NOT STRONG...SOUTHERLY LOW-LEVEL JET IS TRANSPORTING HIGH PRECIPITABLE WATER AIR MASS NORTHWARD OUT OF THE LOWER RIO GRANDE VALLEY...CONTRIBUTING TO CAPE OF 1000-2000 J/KG ABOVE FRONTAL INVERSION ACROSS WEST TEXAS. MOST VIGOROUS STORMS...WITH LARGEST HAIL POTENTIAL...SEEM LIKELY TO REMAIN FOCUSED IN CLOSER PROXIMITY TO FRONT...NORTH/NORTHEAST OF DEL RIO THROUGH 18Z. HOWEVER...MORE MARGINAL SEVERE HAIL THREAT MAY BE SLOW TO DIMINISH IN AREAS TO THE NORTH.. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT...LUB...MAF... 30170182 30950250 31750256 32570207 33100112 33170055 33209995 32859941 32539889 32029915 31259985 30639964 30129947 29639986 29610053 29930147 WWWW From Mcd at goshenarc.org Thu Apr 20 16:21:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:21:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411 WWWW From Mcd at goshenarc.org Thu Apr 20 16:27:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:27:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455 WWWW From Mcd at goshenarc.org Thu Apr 20 16:28:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:28:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411  From Mcd at goshenarc.org Thu Apr 20 16:29:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:29:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455  From Mcd at goshenarc.org Thu Apr 20 16:31:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:31:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411  From Mcd at goshenarc.org Thu Apr 20 16:32:00 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:32:00 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455  From Mcd at goshenarc.org Thu Apr 20 18:23:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:23:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201821 SWOMCD SPC MCD 201821 TXZ000-201945- MESOSCALE DISCUSSION 0582 NWS STORM PREDICTION CENTER NORMAN OK 0121 PM CDT THU APR 20 2006 AREAS AFFECTED...PARTS OF WRN AND CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 219...220... VALID 201821Z - 201945Z HAIL THREAT WILL CONTINUE ACROSS WW AREAS ANOTHER COUPLE OF HOURS ...BUT MAXIMUM HAIL SIZES MAY BEGIN TO DECREASE AS ACTIVITY DEVELOPS TOWARD NORTH CENTRAL/NORTHEAST TEXAS. NEW WWS NORTH/EAST OF 219/220 MAY NOT BE NEEDED. DRY LINE ACROSS SOUTHWEST TEXAS WILL BE MONITORED FOR POSSIBILITY OF INCREASING SEVERE THREAT LATER THIS AFTERNOON. PRIMARY SOUTHERN BRANCH SHORT WAVE TROUGH IS NOW CROSSING THE SOUTHERN ROCKIES...BUT WEAKER DOWNSTREAM IMPULSE APPEARS TO HAVE LIFTED THROUGH THE TEXAS BIG BEND/PECOS VALLEY REGION. MID/UPPER FORCING WITH THIS FEATURE SEEMS LIKELY TO SPREAD NORTHEAST OF THE EDWARDS PLATEAU AND HILL COUNTRY BETWEEN NOW AND 21Z...ACCOMPANIED BY STRONGER CONVECTIVE DEVELOPMENT. MODELS SUGGEST...HOWEVER...THAT THE LOW-LEVEL JET WILL REMAIN DIRECTED NORTHWESTWARD THROUGH THE LOWER RIO GRANDE VALLEY INTO THE PECOS VALLEY. WITH LOSS OF BETTER MOIST INFLOW...ONGOING CONVECTION SEEMS LIKELY TO BECOME INCREASINGLY ELEVATED AS IT PROGRESSES DEEPER INTO CENTRAL TEXAS...AND WEAKER CAPE MAY MITIGATE LARGE HAIL THREAT. AS CONVECTION LIFTS NORTHWARD...MOIST BOUNDARY LAYER WILL BEGIN TO WARM FROM SOUTH CENTRAL TEXAS INTO THE TRANSPECOS REGION...AND SURFACE FRONT MAY REDEVELOP NORTHWARD...CLOSER TO MIDLAND/JUNCTION AND AUSTIN. HOWEVER...STRENGTHENING CAP MAY INHIBIT FURTHER CONVECTIVE DEVELOPMENT UNTIL FORCING WITH UPSTREAM SHORT WAVE BEGINS TO INTERACT WITH DRY LINE ACROSS SOUTHWEST TEXAS LATER THIS AFTERNOON. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX...SJT...LUB...MAF... 32360261 33090168 33209964 33309800 33309667 32549541 31029570 30119771 29829870 30310038 30690162 30210198 29910221 30040266 31350285 WWWW From Mcd at goshenarc.org Thu Apr 20 18:41:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:41:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201839 SWOMCD SPC MCD 201838 TNZ000-GAZ000-ALZ000-MSZ000-LAZ000-ARZ000-202045- MESOSCALE DISCUSSION 0583 NWS STORM PREDICTION CENTER NORMAN OK 0138 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN...NRN/CENTRAL MS CONCERNING...SEVERE THUNDERSTORM WATCH 221... VALID 201838Z - 202045Z CONTINUE ALL OF WW 221. WEAK SURFACE CONVERGENCE COMBINED WITH MID/HIGH CLOUD COVER ARE LIKELY THE MAIN INHIBITING FACTORS FOR NEW DEEP CONVECTIVE DEVELOPMENT OVER NRN AL/SRN MIDDLE TN. HOWEVER...A FEW MORE HRS OF HEATING AND LIKELY CLEARING OF SOME OF THE CLOUD COVER SHOULD AID IN A GREATER POTENTIAL FOR SVR TSTM DEVELOPMENT OVER WW 221 BY MID-AFTERNOON. FURTHER WEST...A WELL DEFINED MCV ON SAT IMAGERY OVER THE ARKLATEX WAS MOVING QUICKLY NEWD. AHEAD OF THIS FEATURE...AN OUTFLOW BOUNDARY WAS WELL DEFINED EXTENDING FROM SERN AR ENEWD INTO NRN MS. OBJECTIVE ANALYSIS INDICATES THAT THE AIRMASS OVER MUCH OF NRN/CENTRAL MS HAS LITTLE REMAINING CINH. WITH THE FOCUSED CONVERGENCE ALONG THE BOUNDARY AND APPROACHING UPPER SUPPORT...SCT CONVECTION MAY DEVELOP OVER NRN/CENTRAL MS IN THE NEXT FEW HRS. MODERATE INSTABILITY AND SHEAR IN PLACE OVER THE AREA WOULD SUPPORT A SVR THREAT WITH ANY TSTMS. THUS...A NEW WW MAY BE NEEDED WEST OF WW 221 IN THE NEXT HOUR OR SO. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN... 35068784 35648756 35598481 34458526 33068577 32918872 32929108 33459119 34499034 WWWW From Mcd at goshenarc.org Thu Apr 20 18:56:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:56:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201853 SWOMCD SPC MCD 201853 NCZ000-SCZ000-TNZ000-GAZ000-202100- MESOSCALE DISCUSSION 0584 NWS STORM PREDICTION CENTER NORMAN OK 0153 PM CDT THU APR 20 2006 AREAS AFFECTED...NERN GA...WRN NC AND UPSTATE SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201853Z - 202100Z CONVECTION WAS GRADUALLY INTENSIFYING OVER FAR SERN TN/NWRN GA UNDER THE INFLUENCE OF AN UPPER WAVE MOVING ACROSS TN AND ON THE NRN END OF INSTABILITY AXIS. WE WILL MONITOR TRENDS FOR ANY INCREASING SVR THREAT OVER THIS AREA...BUT A WW IS NOT EXPECTED ATTM. 18Z SOUNDING FROM ATLANTA SHOWS STEEP LOW-MID LEVEL LAPSE RATES WITH MARGINAL INSTABILITY /MUCAPES AROUND 1000 J/KG /. CONVECTION RECENTLY STRENGTHENING OVER NWRN GA AND SERN TN WAS IN AN AXIS WHERE DEWPTS AND INSTABILITY WHERE SLIGHTLY HIGHER. GIVEN THE SOMEWHAT ORGANIZED NATURE OF THE CONVECTION IT IS POSSIBLE THAT DESPITE SOMEWHAT WEAKER INSTABILITY OVER NERN GA...WRN NC/UPSTATE SC THERE MAY BE SOME MARGINAL SVR HAIL/WIND THREAT THAT DEVELOPS WITH THIS ACTIVITY AS IT MOVES INTO THIS AREA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 36038242 35738357 35298429 35008455 34678466 34228430 34138395 34128331 34778234 35598163 WWWW From Mcd at goshenarc.org Thu Apr 20 20:00:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:00:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201958 SWOMCD SPC MCD 201958 TXZ000-202100- MESOSCALE DISCUSSION 0585 NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT THU APR 20 2006 AREAS AFFECTED...SW THRU CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 219...220... VALID 201958Z - 202100Z SEVERE WEATHER WATCHES WILL LIKELY BE REPLACED WITH A NEW TORNADO WATCH BEFORE 21Z. SOUTHERN STREAM SHORT WAVE TROUGH IS FINALLY BEGINNING TO PROGRESS EAST OF THE SOUTHERN ROCKIES...AND LEADING EDGE OF STRONGER MID-LEVEL COOLING IS ALREADY OVERSPREADING THE TRANS PECOS REGION. THIS...IN CONJUNCTION WITH CONTINUED WARMING OF BOUNDARY LAYER SOUTH OF OUTFLOW ENHANCED SURFACE FRONT...IS CONTRIBUTING TO WEAKENING INHIBITION. MIXED LAYER CAPE ALONG/SOUTH OF FRONT IS CURRENTLY IN EXCESS OF 1500 J/KG...AND WILL INCREASE FURTHER THROUGH THE REMAINDER OF THE AFTERNOON. DRY LINE/FRONTAL INTERSECTION SHIFTING FROM SOUTH OF MIDLAND THROUGH THE JUNCTION AREA BETWEEN 20/21-21/00Z SEEMS MOST PROBABLE FOCUS FOR INTENSE SURFACE BASED CONVECTIVE DEVELOPMENT. WIND PROFILES EXHIBITING PRONOUNCED VEERING WITH HEIGHT IN LOWER-LEVELS WILL BE FAVORABLE FOR SUPERCELLS...PARTICULARLY AS 50 KT 500 MB SPEED MAXIMUM NOSES ACROSS SOUTHWEST TEXAS. RISK OF TORNADOES IS EXPECTED TO INCREASE...ALONG WITH CONTINUING THREAT FOR LARGE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT...MAF... 31000221 31830226 31750099 31340038 31299959 31239871 30679771 29649824 29369952 29920118 30400237 WWWW From Mcd at goshenarc.org Thu Apr 20 20:44:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:44:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202041 SWOMCD SPC MCD 202040 GAZ000-NCZ000-TNZ000-ALZ000-MSZ000-202245- MESOSCALE DISCUSSION 0586 NWS STORM PREDICTION CENTER NORMAN OK 0340 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN AND NRN/WRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 221... VALID 202040Z - 202245Z GREATEST SVR THREAT FOR THE NEXT FEW HRS OVER WW 221 WILL BE ACROSS CENTRAL/SERN PORTIONS OF WW 221 / CENTRAL AND NERN AL / WITH CLUSTER OF STG-SVR STORMS ONGOING. THREAT FOR SVR APPEARS TO BE MOST MARGINAL OVER THE NEXT 1-2 HRS ACROSS SRN MIDDLE TN AS MID LEVEL SUBSIDENCE AND COOLER OUTFLOW AIR REDUCES RENEWED CONVECTIVE POTENTIAL. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM SOUTH OF TUP TO NEAR BHM TO NERN AL/NWRN GA. SVR STORMS HAD DEVELOPED OVER CENTRAL/NERN AL IN REGION OF STRONGEST LOW LEVEL CONVERGENCE IN THE VICINITY OF A MESOLOW TO THE NORTH OF THE BHM AREA. MODERATE INSTABILITY EAST OF THIS ACTIVITY OVER WCENTRAL GA SUGGESTS THAT THE SVR THREAT SHOULD EXTEND EAST OF WW 221. CURRENT STORM MOTIONS WOULD TAKE THE SVR THREAT WITH THIS CLUSTER INTO FAR ECENTRAL AL/WCENTRAL GA BEGINNING AROUND 22Z. THE SVR THREAT SHOULD NOT DEVELOP EWD ACROSS ALL OF NRN GA...AS AN N-S ORIENTED BOUNDARY EXTENDING JUST EAST OF THE ATLANTA METRO AREA SWD TO NEAR MCN SHOULD REMAIN IN PLACE THROUGH THE EVENING HOURS. A WW MAY BE NEEDED FOR NRN GA SHORTLY. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...OHX...BMX...HUN...MEG... 35478481 35488795 34998808 32908830 32938495 33008379 34978339 35008496 WWWW From Mcd at goshenarc.org Thu Apr 20 20:57:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:57:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202054 SWOMCD SPC MCD 202054 TXZ000-NMZ000-202200- MESOSCALE DISCUSSION 0587 NWS STORM PREDICTION CENTER NORMAN OK 0354 PM CDT THU APR 20 2006 AREAS AFFECTED...ERN NM...PARTS OF SW TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 202054Z - 202200Z TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A WW. INSOLATION AND MID-LEVEL COOLING...ASSOCIATED WITH SOUTHERN STREAM TROUGH...HAVE CONTRIBUTED TO VERY STEEP LAPSE RATES ACROSS MUCH OF EASTERN NEW MEXICO. BOUNDARY LAYER IS RATHER DRY...BUT DEEPLY MIXED AND SUFFICIENTLY UNSTABLE FOR CONVECTIVE DEVELOPMENT. ACTIVITY HAS INITIATED ALONG WAVE/OUTFLOW PROPAGATING WESTWARD OUT OF ONGOING CONVECTION ACROSS THE TEXAS SOUTH PLAINS. LOW-LEVEL THERMAL RIDGE AXIS EAST OF THE MOUNTAINS IS ALSO BECOMING FOCUS FOR ACTIVITY IN RESPONSE TO MID-LEVEL FORCING. TENDENCY SHOULD BE FOR STRONGER CONVECTION TO EVENTUALLY DEVELOP SOUTH/SOUTHEASTWARD ALONG EFFECTIVE SURFACE FRONT INTO AREAS WEST OF MIDLAND LATE THIS AFTERNOON. SHEAR IN CLOUD BEARING LAYER SEEMS SUFFICIENT FOR UPDRAFT ROTATION...WHICH MAY ENHANCE RISK OF MARGINALLY SEVERE HAIL...DESPITE LIMITED CAPE. OTHERWISE...DAMAGING WIND GUSTS WILL ALSO BE POSSIBLE IN STRONGEST CELLS. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MAF...ABQ...EPZ... 36520494 35560442 34250395 33550390 32850346 32300311 32000282 31410304 31620401 32780537 34480597 WWWW From Mcd at goshenarc.org Thu Apr 20 21:18:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 17:18:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202116 SWOMCD SPC MCD 202115 ALZ000-TNZ000-MSZ000-ARZ000-LAZ000-202315- MESOSCALE DISCUSSION 0588 NWS STORM PREDICTION CENTER NORMAN OK 0415 PM CDT THU APR 20 2006 AREAS AFFECTED...SERN AR...NRN MS AND SWRN TN CONCERNING...SEVERE THUNDERSTORM WATCH 222... VALID 202115Z - 202315Z TSTMS HAVE HAD TROUBLE SUSTAINING THEMSELVES ACROSS WW 222 OVER THE LAST FEW HRS. HOWEVER...THERE REMAINS A CONTINUED THREAT FOR REDEVELOPMENT OVER THE REGION AS ASCENT REMAINS AHEAD OF WEAK VORT MAX OVER AR AND SURFACE OUTFLOW BOUNDARY AIDS IN SURFACE CONVERGENCE. STORMS THAT DEVELOPED EARLIER OVER THE MS RIVER VALLEY HAVE SINCE DISSIPATED. HOWEVER SFC ANALYSIS SHOWS A MESOLOW OVER SERN AR...AND NEW CONVECTIVE DEVELOPMENT SHOULD CONTINUE TO OCCUR IN THIS REGION. ISOLATED DEVELOPMENT WILL ALSO REMAIN POSSIBLE ALONG AN OUTFLOW BOUNDARY EXTENDING FROM JUST NORTH OF GLH TO CBM. THERMODYNAMIC/SHEAR PARAMETERS REMAIN FAVORABLE FOR A SVR THREAT FOR ANY STORM THAT CAN BE SUSTAINED. ADDITIONALLY...THERE IS SOME POTENTIAL FOR AN ISOLATED SVR STORM TO DEVELOP NORTH OF WW 222 ACROSS SWRN TN WHERE DIFFERENTIAL HEATING BOUNDARY APPEARS TO EXIST. HOWEVER WEAKER INSTABILITY SUGGESTS THAT THE SVR THREAT IN THIS AREA SHOULD REMAIN LIMITED AND ANOTHER WW IS NOT ANTICIPATED. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HUN...MEG...JAN...LZK...SHV... 34978811 35558820 35918902 35019031 34819050 34199220 32949245 33038996 33098838 WWWW From Mcd at goshenarc.org Thu Apr 20 22:56:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 18:56:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202254 SWOMCD SPC MCD 202254 TXZ000-210030- MESOSCALE DISCUSSION 0589 NWS STORM PREDICTION CENTER NORMAN OK 0554 PM CDT THU APR 20 2006 AREAS AFFECTED...SE TX CONCERNING...SEVERE THUNDERSTORM WATCH 223... VALID 202254Z - 210030Z AN MCS IS CURRENTLY ORGANIZING OVER SCNTRL TX JUST EAST OF THE AUSTIN AREA. AS THE COMPLEX MOVES SLOWLY EWD...THE SEVERE THREAT SHOULD INCREASE EAST OF WW 223. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT EXTENDING SWWD FROM NE TX ACROSS THE TX HILL COUNTRY. DEWPOINTS AHEAD OF THE FRONT ARE IN THE MID 60S F WITH AN AXIS OF MODERATE INSTABILITY LOCATED FROM SOUTH TX EXTENDING NNEWD JUST AHEAD OF THE BOUNDARY. AS THE BOUNDARY MOVES SEWD AND A SHORTWAVE-TROUGH APPROACHES FROM THE WEST...CONVECTIVE COVERAGE SHOULD INCREASE ALLOWING THE MCS TO CONTINUE EWD ACROSS SE TX THIS EVENING. OBJECTIVE ANALYSIS CURRENTLY SHOWS A 55 KT MID-LEVEL JET OVER CNTRL TX MOVING EWD. THIS FEATURE WILL BEGIN TO AFFECT SE TX SUSTAINING VERTICAL SHEAR PROFILES SUFFICIENT FOR SEVERE STORMS. HOWEVER...INSTABILITY WILL LIKELY REMAIN WEAKER OVER SE TX KEEPING THE SEVERE THREAT ISOLATED WITH HAIL AND WIND DAMAGE BEING THE PRIMARY THREATS. ..BROYLES.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...EWX... 29169724 29919769 30439746 30699659 30959560 30299485 29339563 WWWW From Mcd at goshenarc.org Thu Apr 20 23:14:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 19:14:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202312 SWOMCD SPC MCD 202311 GAZ000-NCZ000-TNZ000-ALZ000-MSZ000-210115- MESOSCALE DISCUSSION 0590 NWS STORM PREDICTION CENTER NORMAN OK 0611 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL AND NRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 221...225... VALID 202311Z - 210115Z THREAT FOR SVR WILL CONTINUE WITH ORGANIZED CLUSTER ACROSS MUCH OF WW 225 OVER THE NEXT SEVERAL HRS AS IT MOVES INTO THE WRN PORTION OF THE ATL METRO AREA BETWEEN 00-01Z. FURTHER WEST...SVR THREAT SHOULD GRADUALLY DIMINISH OVER WW 221 IN THE NEXT 1-3 HRS. THUS A NEW WW TO REPLACE WW 221 IS NOT LIKELY ATTM...ALTHOUGH LOCAL WFO EXTENSION IS POSSIBLE. LATEST SFC ANALYSIS SHOWS A WELL DEFINED COLD POOL HAS DEVELOPED OVER NERN AL ASSOCIATED WITH SVR TSTM CLUSTER MOVING OUT OF WW 221 INTO WW 225 /NWRN GA/. GIVEN ORGANIZED NATURE OF CONVECTION AND STEEP LOW LEVEL LAPSE RATES /NOTED ON THE 18Z ATL SOUNDING / DMGG WINDS MAY BECOME THE GREATER SVR THREAT AS ACTIVITY MOVES TOWARDS THE ATL METRO AREA. IN THE WAKE OF THIS CLUSTER...SSWLY FLOW OF 10-20 KTS /NOTED ON RECENT BMX VWP DATA/ WAS ORTHOGONAL TO THE OUTFLOW BOUNDARY OVER CENTRAL/NCENTRAL AL. COMBINED WITH MODERATE INSTABILITY AND MARGINAL CINH THIS SHOULD SUPPORT A THREAT FOR REDEVELOPMENT OF TSTMS TO THE EAST OF THE OUTFLOW BOUNDARY OVER NCENTRAL/NERN AL FOR THE NEXT COUPLE OF HRS. GRADUALLY DIMINISHING INSTABILITY AFTER 00Z /WITH LOSS OF HEATING / COMBINED WITH DISPLACEMENT OF CONVECTION FURTHER AWAY FROM THE WWD MOVING OUTFLOW BOUNDARY /NOTED ON BMX RADAR/ WILL LIKELY LEAD TO A DIMINISHING SVR THREAT WITH TIME. THE DIMINISHING INSTABILITY SHOULD ALSO LEAD TO A GRADUAL DEMISE OF ISOLATED SVR STORM NEAR THE AL/MS BORDER...BUT NOT BEFORE THE PASSAGE OF THE WWD MOVING OUTFLOW BOUNDARY INTERACTS WITH THIS STORM. LOCALLY BACKED LOW LEVEL FLOW JUST AHEAD OF THE BOUNDARY MAY AID IN A BRIEF LOCALIZED TORNADO THREAT WITH THIS STORM AROUND 00Z. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...BMX...HUN...MEG...JAN... 35158506 34678822 33368850 33298603 33068613 33008428 34998343 34988503 WWWW From Mcd at goshenarc.org Fri Apr 21 00:38:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 20:38:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210035 SWOMCD SPC MCD 210035 ALZ000-MSZ000-ARZ000-LAZ000-210200- MESOSCALE DISCUSSION 0591 NWS STORM PREDICTION CENTER NORMAN OK 0735 PM CDT THU APR 20 2006 AREAS AFFECTED...SERN AR...NRN MS CONCERNING...SEVERE THUNDERSTORM WATCH 222... VALID 210035Z - 210200Z SVR TSTM THREAT APPEARS TO BE VERY LOW DURING THE REMAINING VALID PORTIONS OF WW 222 THROUGH THE REST OF THE WATCH VALID TIME /02Z/. WILL KEEP PORTIONS OF SERN AR/NRN MS IN THE WW 222 UNTIL THEN IN CASE NEW DEVELOPMENT OCCURS. 00Z JAN SOUNDING SHOWED AN INVERSION CENTERED AROUND 700 MB THAT IS LIKELY PART OF THE REASON CONVECTION HAS FAILED TO BE SUSTAINED OVER MUCH OF WW 222 THIS AFTERNOON/EARLY EVENING. WITH LIMITED CONVERGENCE...WEAK LOW LEVEL WINDS /REF 00Z SHV AND JAN SOUNDINGS/ AND DECREASING INSTABILITY WITH NIGHTFALL...IT IS A VERY LOW PROBABILITY THAT NEW SVR TSTM DEVELOPMENT WILL OCCUR BEFORE 02Z. HOWEVER...SHORT TERM MODELS INDICATE THAT AS UPPER SYSTEM MOVES OUT OF ERN TX...WAA WILL INCREASE. GIVEN RELATIVELY LIMITED CINH OVER NRN LA /PER THE 00Z SHV SOUNDING/ NEW SVR TSTM DEVELOPMENT MAY INCREASE LATER TONIGHT. HOWEVER THIS IS ANTICIPATED TO OCCUR WELL AFTER 02Z...SO WW 222 WILL LIKELY BE ALLOWED TO EXPIRE. ..CROSBIE.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MEG...JAN...LZK... 34908830 34229181 32969174 32898964 33158822 WWWW From Mcd at goshenarc.org Fri Apr 21 00:57:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 20:57:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210055 SWOMCD SPC MCD 210055 GAZ000-SCZ000-NCZ000-TNZ000-ALZ000-210300- MESOSCALE DISCUSSION 0592 NWS STORM PREDICTION CENTER NORMAN OK 0755 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 225... VALID 210055Z - 210300Z SVR THREAT SHOULD NOT EXTEND MUCH EAST OF WW 225 ACROSS NERN GA AND THUS A NEW WW IS NOT EXPECTED. SVR WIND/HAIL THREAT WILL BE MAINLY CONFINED OVER ERN/SRN PORTIONS OF WW 225 FOR THE NEXT 1-2 HRS. HOWEVER ELEVATED TSTMS WITH MARGINALLY SVR HAIL MAY OCCUR WEST OF THIS CONVECTIVE LINE OVER NWRN GA. RADAR IMAGERY SHOWS A WELL DEFINED CONVECTIVE LINE MOVING THROUGH NRN GA /INCLUDING THE ATL METRO AREA/. STEEP LOW LEVEL LAPSE RATES WILL SUPPORT THE THREAT FOR DMGG WINDS WITH THIS LINE FOR THE NEXT 1-2 HRS AS IT MOVES THROUGH THE REMAINDER OF WW 225. THERE MAY BE A MARGINAL SVR THREAT JUST EAST OF WW 225...BUT AREAL EXTENT OF MODEST INSTABILITY SHOULD BE LIMITED TO ONLY A 1-2 ROWS OF COUNTIES EAST OF WW 225 AS STABLE AIR REMAINS OVER NERN/ECENTRAL GA SUPPORTED BY ELY LOW LEVEL FLOW. FURTHER WEST...ALTHOUGH AIRMASS IS WORKED OVER ACROSS NWRN GA BEHIND THE CONVECTIVE LINE...INCREASING LOW LEVEL SSWLY WINDS ATOP MESO-HIGH OVER NWRN GA MAY SUPPORT A MARGINAL HAIL THREAT FOR THE NEXT FEW HRS WITH ANY ADDITIONAL NEW TSTM DEVELOPMENT. THIS AREA MAY BE CLEARED FROM WW 225 BY 02Z IF NEW TSTM INITIATION FAILS TO OCCUR BEFORE THEN. ..CROSBIE.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...BMX...HUN... 34998531 33028612 33038414 33138323 34988316 WWWW From Mcd at goshenarc.org Fri Apr 21 02:34:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 22:34:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210231 SWOMCD SPC MCD 210231 TNZ000-MSZ000-MOZ000-ARZ000-TXZ000-210400- MESOSCALE DISCUSSION 0593 NWS STORM PREDICTION CENTER NORMAN OK 0931 PM CDT THU APR 20 2006 AREAS AFFECTED...WRN TN / FAR NW MS / MUCH OF AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 210231Z - 210400Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE THROUGH THE EVENING HOURS AND OVERNIGHT...WITH A THREAT OF SOME SVR HAIL. A WW COULD BE REQUIRED SOON. LATEST UPPER AIR ANALYSIS AS WELL AS OBJECTIVE ANALYSIS SHOWS 700 MB TEMPERATURE GRADIENT ACROSS NRN MS INTO SRN AR / NRN LA. ALTHOUGH MODERATELY UNSTABLE SOUTH OF THIS LINE...CAPPING EXISTS AS SEEN ON 00Z JAN SOUNDING AS WELL AS TAMDAR DATA ACROSS CENTRAL MS...DECREASING TO THE NORTH WITH NO CAP ON COOL SIDE OF BOUNDARY FROM WRN TN ACROSS FAR NRN MS AND INTO CENTRAL AR. MODERATE WARM ADVECTION ALONG WITH APPROACHING UPPER VORT ASSOCIATED WITH E TX CONVECTION WILL LIKELY ALLOW FOR AN INCREASE IN STORMS ACROSS THE MCD AREA. ISOLATED TO SCATTERED SVR HAIL WILL BE THE MAIN THREAT. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...MEG...JAN...LZK...SHV... 33709124 34268958 35008829 35388715 36558711 36458834 36219006 35039267 34249411 33669420 33289369 33289259 WWWW From Mcd at goshenarc.org Fri Apr 21 03:56:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 23:56:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210354 SWOMCD SPC MCD 210353 ALZ000-TNZ000-MSZ000-210530- MESOSCALE DISCUSSION 0594 NWS STORM PREDICTION CENTER NORMAN OK 1053 PM CDT THU APR 20 2006 AREAS AFFECTED...CENTRAL AND NRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 228... VALID 210353Z - 210530Z SEVERE THREAT APPEARS TO BE DECREASING AS OF 330Z ACROSS MUCH OF WW 228...HOWEVER...ADDITIONAL DEVELOPMENT MAY OCCUR LATER THIS EVENING INTO THE EARLY MORNING HOURS OVER NWRN AL. LARGE HAIL WOULD BE THE MAIN SVR THREAT. ISOLATED STORMS PERSIST WITHIN WARM ADVECTION ZONE LYING NW-SE ACROSS AL. MOST OF THE AIRMASS E OF THIS BOUNDARY HAS BEEN AFFECTED BY COOL OUTFLOW INTO NERN AL AND NWRN GA...THUS STORMS HAVE SHOWN WEAKENING TRENDS AS THEY MOVE NEWD. AREA WIND PROFILERS/VWPS DO SHOW INCREASING LOW LEVEL FLOW /850 MB/ AROUND 15-20 KTS WHICH WILL CONTINUE TO FEED STORMS ALONG THE WARM FRONTAL/OUTFLOW BOUNDARY FOR SEVERAL MORE HOURS...ALTHOUGH COMBINATION OF CONTINUED WARM ADVECTION ALOFT WITH COOLING BOUNDARY LAYER WILL LIKELY CAUSE STORMS TO EVENTUALLY DIE OVER CENTRAL AND ERN AL. GREATER THREAT FOR SVR EXIST ACROSS NWRN AL...IN CLOSER PROXIMITY TO INSTABILITY POOL NOW OVER NRN MS. APPROACHING UPPER WAVE WILL CAUSE STORMS TO INCREASE TO THE WEST OF WW 228 OVER THE NEXT SEVERAL HOURS...AND A FEW OF THESE STORMS MAY MAKE IT INTO NWRN AL LATER TONIGHT WITH A LARGE HAIL THREAT. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG... 34998815 35008685 33568632 32648621 32488664 33008825 WWWW From Mcd at goshenarc.org Fri Apr 21 04:29:36 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 00:29:36 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210427 SWOMCD SPC MCD 210426 LAZ000-TXZ000-210600- MESOSCALE DISCUSSION 0595 NWS STORM PREDICTION CENTER NORMAN OK 1126 PM CDT THU APR 20 2006 AREAS AFFECTED...EAST TX/NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 227... VALID 210426Z - 210600Z A MARGINAL SEVERE THREAT WILL LIKELY CONTINUE ACROSS THE ERN PART OF WW 227 OVER THE NEXT FEW HOURS. THE SEVERE THREAT MAY EXPAND INTO NRN LA AS THE MCS DRIFTS EWD OVERNIGHT. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT MOVING SEWD ACROSS EAST TX WITH A MOIST AXIS EXTENDING NWD THROUGH THE SABINE RIVER VALLEY INTO NW LA. SFC DEWPOINTS ALONG THE MOIST AXIS ARE IN THE MID TO UPPER 60S F AND THIS IS HELPING TO MAINTAIN MODERATE INSTABILITY ACROSS WRN AND CNTRL LA. IN ADDITION...REGIONAL PROFILERS SHOW 40-45 KT OF 0-6 KM SHEAR SUGGESTING THE SHEAR AND INSTABILITY MAY BE ENOUGH FOR A MARGINAL SEVERE THREAT OVERNIGHT. HAIL AND STRONG WIND GUSTS WOULD BE LIKELY WITH THE STRONGER CELLS AS THE MCS MOVES INTO NRN AND CNTRL LA AFTER 06Z. ..BROYLES.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LCH...SHV...HGX... 30339389 30419480 30789528 31389526 32379418 32749254 32139154 31019235 WWWW From Mcd at goshenarc.org Fri Apr 21 05:06:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 01:06:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210504 SWOMCD SPC MCD 210504 ALZ000-TNZ000-MSZ000-210700- MESOSCALE DISCUSSION 0596 NWS STORM PREDICTION CENTER NORMAN OK 1204 AM CDT FRI APR 21 2006 AREAS AFFECTED...NERN MS / SWRN TN / EXTREME NWRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210504Z - 210700Z THREAT FOR WIND DAMAGE AND/OR ISOLATED TORNADOES APPEARS TO BE INCREASING. LARGE HAIL THREAT MAY BE ENHANCED AS WELL. LATEST RADAR SHOWS ROTATION DEVELOPING WITH CELLS OVER NRN MS / SWRN TN. SURFACE ANALYSIS INDICATES LOWER 70S TEMPERATURES INTO NRN MS...WHICH WHEN COMBINED WITH MID 60S DEWPOINTS YIELDS SURFACE BASED PARCELS WITH LITTLE CIN IN MODERATELY UNSTABLE ENVIRONMENT. FURTHER...AREA VAD WIND PROFILES ARE SHOWING STRONGER LOW LEVEL SHEAR THAN CURRENTLY ANALYZED BY RUC. WHILE THEY MAY BE A LITTLE TOO STRONG WHEN COMPARED TO LOCAL ACARS/TAMDAR SOUNDINGS...IT APPEARS AT LEAST 20-25 KT VEERING LOW LEVEL FLOW EXIST OFF THE SURFACE WHICH IS RESULTING IN 0-1 SRH VALUES IN EXCESS OF 250 M2/S2. THUS...AN ISOLATED TORNADO CANNOT BE RULED OUT...WITH THE MAIN LIMITING FACTOR BEING SURFACE DECOUPLING AS REFLECTED IN WEAK SURFACE WIND SPEEDS OF 5 KTS OR LESS. A POTENTIAL SIGN OF INCREASED TORNADO THREAT MAY BE AN INCREASE IN SURFACE WINDS AHEAD OF STORMS AND WITHIN RELATIVELY WARMER / 70S / TEMPERATURES. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG...JAN... 33859016 34349025 34958944 35298897 35448815 35248788 34538789 34128817 WWWW From Mcd at goshenarc.org Fri Apr 21 06:14:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 02:14:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210612 SWOMCD SPC MCD 210612 TXZ000-210815- MESOSCALE DISCUSSION 0597 NWS STORM PREDICTION CENTER NORMAN OK 0112 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS CENTRAL/S-CENTRAL TX. CONCERNING...SEVERE THUNDERSTORM WATCH 230... VALID 210612Z - 210815Z TSTMS CONTINUE TO INCREASE IN COVERAGE ACROSS PORTIONS CENTRAL/S-CENTRAL TX -- FROM NERN HILL COUNTRY W ACT...SWWD ACROSS HILL COUNTRY AND LOWLANDS NE DRT. ALTHOUGH ANY OF THIS ACTIVITY MAY PRODUCE HAIL AS IT MOVES EWD AND SEWD INTO MORE UNSTABLE INFLOW...MAIN SEVERE POTENTIAL WILL BE CONCENTRATED ACROSS AREA BETWEEN AUS-COT...INCLUDING SAT. WW 230 IS THEREFORE REQUIRED. SFC MESOANALYSIS INDICATES QUASISTATIONARY BAROCLINIC ZONE FROM ABOUT 20 S DRT....ENEWD THROUGH HDO...SAT...IAH. THIS BOUNDARY HAS BEEN REINFORCED BY OUTFLOWS FROM EARLIER CONVECTION. CONVECTION DEVELOPING/INCREASING IN COVERAGE TO ITS N DOES NOT APPEAR TO BE SFC-BASED...GIVEN STATIC STABILITY APPARENT NEAR SFC IN MODIFIED RAOBS AND RUC FCST SOUNDINGS. HOWEVER...COMBINATION OF STEEP MIDLEVEL LAPSE RATES -- APPARENT ON 00Z DRT RAOB -- AND LOW LEVEL WAA/MOIST ADVECTION ATOP STABLE LAYER -- CONTRIBUTES TO FAVORABLE BUOYANCY. ELEVATED MUCAPES 1000-1500 J/KG ARE EVIDENT WITHIN ABOUT 70-90 NM OF BOUNDARY...DECREASING GRADUALLY FARTHER NWD OVER CENTRAL TX. EFFECTIVE SHEAR VECTOR SPEEDS OF 40-60 KT SUGGEST SOME POTENTIAL FOR SUPERCELL STRUCTURES...ESPECIALLY OVER S-CENTRAL TX VICINITY SAT...WHICH WOULD ENHANCE LARGE HAIL POTENTIAL. TSTMS MOVING ALONG AND S OF BOUNDARY WILL BE NEARLY SFC-BASED...AND MAY PRODUCE DAMAGING WIND AS WELL. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...CRP...EWX...SJT... 29100080 29900037 30429949 31079837 30999775 30609688 30339662 29839657 29029698 28519861 28000001 28140006 28250026 28480035 28670048 28930062 29060065 WWWW From Mcd at goshenarc.org Fri Apr 21 07:18:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 03:18:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210716 SWOMCD SPC MCD 210715 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-LAZ000-210915- MESOSCALE DISCUSSION 0598 NWS STORM PREDICTION CENTER NORMAN OK 0215 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS SRN/ERN AR...NRN LA...NRN MS...TN...NRN AL...NWRN GA. CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210715Z - 210915Z WW SHOULD BE CONTINUED ALONG/NE OF LA/AR MCS. AREAS SE AND E OF WW ARE BEING MONITORED FOR POSSIBILITY OF ADDITIONAL WW. ORGANIZED COMPLEXES OF STRONG-SEVERE TSTMS CONTINUE TO MOVE ACROSS SWRN PORTIONS WW...FROM E-CENTRAL AR TO N-CENTRAL LA -- AND ALSO ACROSS ERN PORTIONS WRN-MIDDLE TN. MAIN THREAT CONTINUES TO BE HAIL...ALTHOUGH OCCASIONAL DAMAGING GUSTS ARE POSSIBLE ACROSS SERN AR...NERN LA AND NWRN MS GIVEN NEARLY SFC-BASED INFLOW LAYERS EVIDENT IN MODIFIED RUC SOUNDINGS. RUC WIND PROFILES IN LOW LEVELS APPEAR TOO WEAK ACROSS NRN MS COMPARED TO OBSERVED VWP...WITH RADAR DERIVED 0-1 KM SRH REACHING 300-400 J/KG RANGE AND OBSERVED 0-6 KM AGL SHEAR AROUND 50 KT. THIS WILL FAVOR SUPERCELL STRUCTURES AND CONTINUED RISK OF LARGE HAIL. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY FROM EARLIER MCS...FROM MCN...20 W BHM...20 WNW MSL. THIS BOUNDARY HAS BECOME QUASISTATIONARY. ISOLATED TO WIDELY SCATTERED TSTMS HAVE DEVELOPED FROM AL/TN BORDER AREA ENEWD ALMOST TO TYS. THIS ACTIVITY IS OCCURRING IN ZONE OF ELEVATED LOW LEVEL WAA AND MOIST ADVECTION...WELL N OF SFC OUTFLOW BOUNDARY. AS ELEVATED AIR MASS CONTINUES TO DESTABILIZE NEWD ACROSS SRN-MIDDLE TN...ERN TN AND EXTREME NWRN GA...CONVECTIVE COVERAGE SHOULD CONTINUE TO INCREASE. NEITHER EFFECTIVE SHEAR NOR ELEVATED BUOYANCY SHOULD BE AS LARGE AS FARTHER W IN WW...HOWEVER OCCASIONAL SEVERE HAIL IS POSSIBLE FROM THIS ACTIVITY AS IT MOVES NEWD 20-25 KT. ISOLATED TSTMS PRODUCED HAIL TO NEAR .88 INCH DIAMETER INVOF TCL...WITH LEFT SPLIT MOVING NNEWD ACROSS AREA BETWEEN TCL-HSV. ALTHOUGH AIR MASS HAS DIABATICALLY STABILIZED IN SKIN LAYER NEAR SFC...EFFECTIVE LIFTED PARCELS STILL ARE SFC-BASED...AMIDST ENOUGH DEEP-LAYER SHEAR TO SUPPORT BOTH SUPERCELLS AND ORGANIZED MULTICELLS. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN...LZK...SHV... 32299338 33049253 34809148 36598573 36458455 35678404 34658485 33648609 33248759 34488754 WWWW From Mcd at goshenarc.org Fri Apr 21 09:21:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 05:21:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210913 SWOMCD SPC MCD 210913 TXZ000-211115- MESOSCALE DISCUSSION 0599 NWS STORM PREDICTION CENTER NORMAN OK 0413 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/SE TX. CONCERNING...SEVERE THUNDERSTORM WATCH 230... VALID 210913Z - 211115Z QUASI-LINEAR CONVECTIVE COMPLEX HAS EVOLVED FROM PREVIOUSLY BROKEN BAND OF DISCRETE CELLS AND...AS OF 845Z...EXTENDED FROM SRN FRINGES SAT METRO AREA NEWD TO NRN BRAZOS COUNTY. MOST VIGOROUS CONVECTION SHOULD CROSS AREA FROM VCT THROUGH HOU. ALTHOUGH A FEW ELEVATED TSTMS MAY DEVELOP OVER REINFORCING OUTFLOW POOL...SEVERE THREAT SHOULD BE RELATIVELY MEAGER WITH SUCH ACTIVITY...AND WW MAY BE CLEARED FROM NW-SE AS MCS MOVES BY. PROSPECTIVE PATH OF MCS -- TOWARD MIDDLE-UPPER TX COAST -- MAY REQUIRE WW SOON. AIR MASS AHEAD OF THESE TSTMS...ACROSS SE TX...APPEARS FAVORABLE FOR MCS TO MOVE GENERALLY ESEWD DURING NEXT FEW HOURS...PRODUCING OCCASIONAL HAIL. DAMAGING GUSTS ALSO ARE POSSIBLE IN MIDDLE-SRN PORTION OF MCS...WHERE NEAR-SFC STABLE LAYER IS SHALLOWEST...AND MOST PENETRABLE BY STRONG-SEVERE DOWNDRAFTS. SFC MESOANALYSIS SHOWS QUASISTATIONARY BAROCLINIC BOUNDARY FROM NEAR SABINE/NEWTON COUNTY LINE WSWWD NEAR IAH...THEN APPROXIMATELY 50 N VCT...BEFORE BEING OVERTAKEN BY SRN PORTION OF MCS. MODIFIED RUC SOUNDINGS SHOW LIFTED PARCELS S OF BOUNDARY ARE SFC-BASED OR NEARLY SO. HOWEVER...THESE PARCELS ARE RESTRICTED FROM ASCENT BY CAPPING IN 750-850 MB LAYER...WHICH INCREASES WITH SRN EXTENT. LLJ HAS INCREASED TO 40 KT S OF MCS...PER CRP VWP TRENDS. MCS MAY BACKBUILD SLGTLY AMIDST FAVORABLE STORM-RELATIVE INFLOW AND MUCAPES AROUND 1500 J/KG. HOWEVER...ANTICIPATE MAJORITY OF ACTIVITY WILL RESULT FROM FORCED ASCENT TO LFC...ALONG THAT PORTION OF OUTFLOW EDGE IN AND S OF SFC FRONTAL ZONE. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...CRP...EWX... 29209947 29429891 29749811 30259751 30649699 30799663 30509549 29649502 28729562 28109671 28009752 28399917 28529971 28610000 28830010 28920006 29029989  From Mcd at goshenarc.org Fri Apr 21 09:39:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 05:39:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210936 SWOMCD SPC MCD 210936 TNZ000-ALZ000-MSZ000-211100- MESOSCALE DISCUSSION 0600 NWS STORM PREDICTION CENTER NORMAN OK 0436 AM CDT FRI APR 21 2006 AREAS AFFECTED...NRN MS...WRN PORTIONS OF WRN AND MIDDLE TN...NW AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210936Z - 211100Z MAIN THREAT FOR ISOLATED SEVERE HAIL/WIND SHOULD BE FOCUSED ACROSS FAR NRN MS WHERE OUTFLOW FROM W MERGES WITH E-W BOUNDARY JUST N OF THE TN BORDER. HOWEVER...INSTABILITY IS EXPECTED TO GRADUALLY DIMINISH THROUGH THE MORNING...AND THE OVERALL SEVERE THREAT MAY DIMINISH TO THE POINT THAT ANOTHER WW IS NOT NECESSARY. ONE MCS WITH A WEAK BOW STRUCTURE IS MOVING ENEWD INTO NW MS...WHILE OTHER CONVECTION CONTINUES ALONG A DIFFUSE E-W BOUNDARY ACROSS SRN PORTIONS OF WRN AND MIDDLE TN. THE WRN MCS SHOULD CONTINUE ACROSS NRN MS FOR THE NEXT COUPLE OF HOURS...WITH THE THREAT FOR SPORADIC HAIL AND STRONG WIND GUSTS. HOWEVER...THE ERN PROGRESS OF THE STRONGER STORMS MAY BE LIMITED LATER THIS MORNING BY GRADUALLY DIMINISHING INSTABILITY OVER NRN AL AND MIDDLE TN. GIVEN THE WEAKENING TRENDS NOTED IN RADAR/SATELLITE IMAGERY...AND THE FORECAST OF DIMINISHING INSTABILITY WITH TIME...AN ADDITIONAL SEVERE THUNDERSTORM WATCH MAY NOT BE NEEDED AFTER WW 229 EXPIRES AT 10Z. ..THOMPSON.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...OHX...BMX...HUN...JAN... 35478933 35628928 33808928 33959006 34429018 35099004 35498957 35668827 35588700 35338665 34728656 34348669 33908767 WWWW From Mcd at goshenarc.org Fri Apr 21 10:03:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 06:03:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211000 SWOMCD SPC MCD 211000 COR ALZ000-TNZ000-MSZ000-211100- MESOSCALE DISCUSSION 0600 NWS STORM PREDICTION CENTER NORMAN OK 0500 AM CDT FRI APR 21 2006 AREAS AFFECTED...NRN MS...WRN PORTIONS OF WRN AND MIDDLE TN...NW AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 211000Z - 211100Z CORRECTED FOR SPURIOUS LINE SEGMENT MAIN THREAT FOR ISOLATED SEVERE HAIL/WIND SHOULD BE FOCUSED ACROSS FAR NRN MS WHERE OUTFLOW FROM W MERGES WITH E-W BOUNDARY JUST N OF THE TN BORDER. HOWEVER...INSTABILITY IS EXPECTED TO GRADUALLY DIMINISH THROUGH THE MORNING...AND THE OVERALL SEVERE THREAT MAY DIMINISH TO THE POINT THAT ANOTHER WW IS NOT NECESSARY. ONE MCS WITH A WEAK BOW STRUCTURE IS MOVING ENEWD INTO NW MS...WHILE OTHER CONVECTION CONTINUES ALONG A DIFFUSE E-W BOUNDARY ACROSS SRN PORTIONS OF WRN AND MIDDLE TN. THE WRN MCS SHOULD CONTINUE ACROSS NRN MS FOR THE NEXT COUPLE OF HOURS...WITH THE THREAT FOR SPORADIC HAIL AND STRONG WIND GUSTS. HOWEVER...THE ERN PROGRESS OF THE STRONGER STORMS MAY BE LIMITED LATER THIS MORNING BY GRADUALLY DIMINISHING INSTABILITY OVER NRN AL AND MIDDLE TN. GIVEN THE WEAKENING TRENDS NOTED IN RADAR/SATELLITE IMAGERY...AND THE FORECAST OF DIMINISHING INSTABILITY WITH TIME...AN ADDITIONAL SEVERE THUNDERSTORM WATCH MAY NOT BE NEEDED AFTER WW 229 EXPIRES AT 10Z. ..THOMPSON.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG...JAN... 33808928 33959006 34429018 35099004 35498957 35668827 35588700 35338665 34728656 34348669 33908767 WWWW From Mcd at goshenarc.org Fri Apr 21 11:41:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 07:41:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211139 SWOMCD SPC MCD 211138 LAZ000-TXZ000-211345- MESOSCALE DISCUSSION 0601 NWS STORM PREDICTION CENTER NORMAN OK 0638 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS SE TX...EXTREME SWRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 231... VALID 211138Z - 211345Z ORGANIZED MCS/BOW WITH SMALLER EMBEDDED LEWP FEATURES WILL CONTINUE MOVING ESEWD ACROSS MID/UPPER TX COASTAL PLAIN. TSTMS SHOULD MOVE OFFSHORE ARANSAS/CALHOUN/MATAGORDA/BRAZORIA/GALVESTON COUNTIES BETWEEN 12Z-13Z...AND OFFSHORE CHAMBERS COUNTY BY ABOUT 14Z. MRGLLY SEVERE HAIL AND 50-52 KT GUSTS HAVE BEEN REPORTED WITH THIS ACTIVITY IN THE PAST 1-2 HOURS. POTENTIAL FOR DAMAGING GUSTS AND OCCASIONAL HAIL REMAINS WITH THIS MCS AS IT MOVES THROUGH FAVORABLY MOIST AIR MASS ALONG AND S OF QUASISTATIONARY BAROCLINIC ZONE...ANALYZED AT 11Z FROM NRN PORTIONS HOU METRO AREA NEWD PAST POE. CONVECTION WILL BE SUPPORTED BY SFC DEW POINTS LOW 70S F IN INFLOW LAYER...WITH SBCAPES 1500-2500 J/KG S OF BOUNDARY...AND STRONGLY FORCED ASCENT TO LFC ALONG LEADING PORTION OF OUTFLOW SLAB. KINEMATIC PROFILES REMAIN FAVORABLE WITH 100-200 J/KG OF 0-1 KM SRH...40-50 KT 0-6 KM SHEAR. NRN PORTION OF THIS COMPLEX MAY AFFECT PORTIONS HARDIN/JEFFERSON/ORANGE COUNTIES JUST E OF WW...AS WELL AS CAMERON PARISH. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...HGX...CRP... 28829684 28769632 28989588 29339562 29709540 29979540 30269555 30369531 30119436 30019358 29759318 29449329 29179444 28299596 28279666 WWWW From Mcd at goshenarc.org Fri Apr 21 14:53:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 10:53:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211451 SWOMCD SPC MCD 211451 MSZ000-LAZ000-211615- MESOSCALE DISCUSSION 0602 NWS STORM PREDICTION CENTER NORMAN OK 0951 AM CDT FRI APR 21 2006 AREAS AFFECTED...ERN LA...CNTRL/SRN MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211451Z - 211615Z WW WILL PROBABLY BE ISSUED SHORTLY. FORCING ASSOCIATED WITH SOUTHERN BRANCH IMPULSE IS CONTRIBUTING TO MAINTENANCE OF MESOSCALE CONVECTIVE SYSTEM...AND THIS SEEMS LIKELY TO REMAIN THE CASE AS IT SPREADS INTO THE LOWER MISSISSIPPI VALLEY THROUGH THE MID DAY HOURS. BOUNDARY LAYER AHEAD OF THIS SYSTEM... AND SOUTH OF OLD OUTFLOW BOUNDARY EXTENDING ACROSS NORTHEASTERN LOUISIANA THROUGH CENTRAL MISSISSIPPI INTO NORTH CENTRAL ALABAMA...REMAINS MOIST...AND WILL BECOMING INCREASINGLY UNSTABLE WITH HEATING. MIXED LAYER CAPE IS EXPECTED TO INCREASE IN EXCESS OF 2000 J/KG...AND SEVERE THREAT SEEMS LIKELY TO INCREASE AS CONVERGENCE ALONG OUTFLOWS SUPPORT INCREASINGLY SURFACE BASED CONVECTIVE DEVELOPMENT. SOUTHERLY LOW-LEVEL JET IS STILL ONLY ON THE ORDER OF 20-25 KT... BUT APPEARS TO BE STRENGTHENING FROM SOUTH CENTRAL LOUISIANA INTO CENTRAL MISSISSIPPI. BENEATH 40+ KT CYCLONIC MID-LEVEL FLOW...THIS WILL PROVIDE FAVORABLY STRONG MEAN FLOW/SHEAR REGIME FOR DAMAGING WINDS. ISOLATED SUPERCELLS ARE ALSO POSSIBLE...WITH ENHANCED RISK OF LARGE HAIL...POSSIBLY TORNADOES. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LCH... 32569148 32779086 32849026 33098966 33188874 32218874 31758908 31098937 30498951 29938979 29708972 29499024 29449087 29699171 29789230 30029265 30449261 30979242 31339195 31839168 32169164 WWWW From Mcd at goshenarc.org Fri Apr 21 17:20:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 13:20:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211717 SWOMCD SPC MCD 211717 NCZ000-TNZ000-GAZ000-ALZ000-211845- MESOSCALE DISCUSSION 0603 NWS STORM PREDICTION CENTER NORMAN OK 1217 PM CDT FRI APR 21 2006 AREAS AFFECTED...NRN/CNTRL AL...ERN TN...NW GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211717Z - 211845Z SLOW INCREASE IN CONVECTIVE DEVELOPMENT IS ALREADY ONGOING. THIS SHOULD INTENSIFY FURTHER THIS AFTERNOON. TRENDS ARE BEING MONITORED FOR AN INCREASING SEVERE THREAT...AND THE POSSIBILITY OF A WW. INITIAL SOUTHERN BRANCH IMPULSE CONTINUES TO LIFT NORTHEASTWARD THROUGH THE UPPER TENNESSEE VALLEY. 50+ KT 500 MB JET STREAK SEEMS TO BE ACCOMPANYING THIS FEATURE...AND MAIN CONVECTIVE DEVELOPMENT ASSOCIATED WITH STRONGER MID-LEVEL FORCING IS BEGINNING TO SHIFT TOWARD THE UPPER OHIO VALLEY/NORTH CENTRAL APPALACHIANS. HOWEVER...IN WAKE OF THIS FEATURE...AND AHEAD OF LOWER MISSISSIPPI VALLEY SHORT WAVE TROUGH...CONFLUENT LOW-LEVEL REGIME MAY BECOME FOCUS FOR INCREASING THUNDERSTORM ACTIVITY INTO THE 19-20Z TIME FRAME. MOIST BOUNDARY LAYER FROM THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS INTO NORTHERN ALABAMA IS DEEPENING WITH INSOLATION. AS TEMPERATURES APPROACH THE LOWER 80S...MIXED LAYER CAPE IS EXPECTED TO EXCEED 1000 J/KG. THIS SHOULD BE SUFFICIENT FOR VIGOROUS UPDRAFTS IN FAVORABLY SHEARED ENVIRONMENT FOR MID-LEVEL UPDRAFT ROTATION. LARGE HAIL MAY BE PRIMARY SEVERE THREAT. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...OHX...BMX...HUN... 34998618 35658598 36368452 36338366 35578355 35378371 34358429 33538489 32768617 32358731 32538818 33158816 34138711 WWWW From Mcd at goshenarc.org Fri Apr 21 17:54:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 13:54:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211752 SWOMCD SPC MCD 211752 ALZ000-FLZ000-MSZ000-LAZ000-211915- MESOSCALE DISCUSSION 0604 NWS STORM PREDICTION CENTER NORMAN OK 1252 PM CDT FRI APR 21 2006 AREAS AFFECTED...SE LA...CNTRL/SRN MS...INTO CNTRL/SRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 232... VALID 211752Z - 211915Z CONTINUE WW. CENTRAL/SOUTHERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE ARE BEING MONITORED FOR A POSSIBLE ADDITIONAL WW LATER THIS AFTERNOON CONGLOMERATE SURFACE COLD POOL IS PROGRESSING EAST OF THE NATCHEZ/ BATON ROUGE/LAFAYETTE AREAS. THIS FEATURE IS BECOMING A FOCUS FOR INTENSIFYING CONVECTION...WITH ADDITIONAL SCATTERED STORMS DEVELOPING/INCREASING IN COVERAGE AHEAD OF IT ACROSS MUCH OF CENTRAL/SOUTHERN MISSISSIPPI AND SOUTHEAST LOUISIANA. ACTIVITY IS NOW LIKELY BASED IN MOIST BOUNDARY LAYER...WHICH IS BECOMING INCREASINGLY UNSTABLE WITH CONTINUED INSOLATION. THIS AIR MASS EXTENDS EASTWARD THROUGH MUCH OF CENTRAL/SOUTHERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE...WHERE CAPE MAY APPROACH 2000 J/KG BY PEAK HEATING. DESTABILIZATION AND FORCING/SHEAR ASSOCIATED UPSTREAM SOUTHERN BRANCH TROUGH/JET STREAK ARE EXPECTED TO SUPPORT CONTINUED EVOLUTION OF A LARGE CONVECTIVE CLUSTER. AS SURFACE COLD POOL STRENGTHENS... EASTWARD ACCELERATION ACROSS SOUTHERN MISSISSIPPI AT 30-40+ KT APPEARS POSSIBLE...ACCOMPANIED BY INCREASING THREAT FOR DAMAGING WINDS. GUST FRONT MAY ADVANCE EAST OF THE EASTERN MISSISSIPPI BORDER BY 21-22Z. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MOB...JAN...LIX... 32489031 32998906 33018834 33078771 32778738 32338709 31798710 31228726 30838735 30188768 29758804 29428857 29088939 28969007 29089072 30419060 31009088 WWWW From Mcd at goshenarc.org Fri Apr 21 18:51:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 14:51:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211849 SWOMCD SPC MCD 211848 FLZ000-GAZ000-212045- MESOSCALE DISCUSSION 0605 NWS STORM PREDICTION CENTER NORMAN OK 0148 PM CDT FRI APR 21 2006 AREAS AFFECTED...INTERIOR PORTIONS OF NORTHERN/CENTRAL FL AND FAR SOUTHERN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211848Z - 212045Z THREAT FOR ISOLATED DAMAGING WIND GUSTS/HAIL AND PERHAPS A TORNADO WILL EXIST WITH THUNDERSTORM DEVELOPMENT THIS AFTERNOON ACROSS INTERIOR PORTIONS OF THE NORTHERN/CENTRAL FL PENINSULA INTO SOUTHERN GA. A WATCH IS NOT EXPECTED. WITH LITTLE OR NO BACKGROUND FORCING FOR ASCENT...SEABREEZE BOUNDARY INTERACTIONS ARE LEADING TO DEEPENING CU FIELD ACROSS INTERIOR PORTIONS OF NORTHERN/CENTRAL FL PENINSULA...WITH FIRST STORM DEVELOPMENT BETWEEN OCALA AND BROOKSVILLE FL. INCREASING THUNDERSTORM COVERAGE IS EXPECTED OVER THE NEXT FEW HOURS ACROSS INTERIOR FL INTO SOUTHERN GA...WITH STRONG/SEVERE STORMS POSSIBLE THROUGH EARLY EVENING. A WARM/MOIST BOUNDARY LAYER...COUPLED WITH SUFFICIENTLY COOL TEMPERATURES ALOFT...WILL LEAD TO MLCAPE OF 1500-2000 J/KG PER CURRENT TRENDS/ADJUSTED RUC SOUNDINGS. ALTHOUGH MODERATE INSTABILITY...PRIMARY LIMITING FACTOR FOR AN ORGANIZED SEVERE THREAT WILL BE RATHER WEAK VERTICAL SHEAR /15 KTS OR LESS 0-6 KM PER CURRENT WSR-88D VWPS AND REGIONAL 12Z RAOBS/. A PULSE-TYPE/EPISODIC SEVERE POTENTIAL WOULD BE THE NORM WITH THE SLOW MOVING STORMS...WITH THREATS FOR DAMAGING WET MICROBURSTS/HAIL AND PERHAPS A TORNADO VIA BOUNDARY INTERACTIONS. MARGINAL/ISOLATED NATURE OF THE OVERALL THREAT SUGGESTS A WATCH WILL NOT BE NEEDED. ..GUYER.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MLB...TBW...JAX...TAE... 30578310 30928259 30538175 28148098 27668186 28438241 29938298 WWWW From Mcd at goshenarc.org Fri Apr 21 20:43:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 16:43:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212040 SWOMCD SPC MCD 212039 GAZ000-ALZ000-FLZ000-212145- MESOSCALE DISCUSSION 0606 NWS STORM PREDICTION CENTER NORMAN OK 0339 PM CDT FRI APR 21 2006 AREAS AFFECTED...MS...GA...AL...WRN FL PNHDL CONCERNING...SEVERE THUNDERSTORM WATCH 232...233... VALID 212039Z - 212145Z REMAINING VALID PORTION OF WW 232 MAY BE ALLOWED TO EXPIRE AT 21Z. CONTINUE REMAINING VALID PORTION OF WW 233. PARTS OF SOUTHERN/ EASTERN AL INTO WESTERN GEORGIA ARE BEING MONITORED FOR POSSIBLE ADDITIONAL WW. WELL ORGANIZED CONVECTIVE SYSTEM HAS YET TO EVOLVE...BUT STILL APPEARS POSSIBLE LATE THIS AFTERNOON AS MID-LEVEL FORCING ASSOCIATED WITH A SOUTHERN BRANCH SHORT WAVE TROUGH LIFTS OUT OF LOUISIANA/ MISSISSIPPI TOWARD THE SOUTHERN APPALACHIANS. INFLUX OF DRIER LOWER /MID TROPOSPHERIC AIR AND DOWNWARD MIXING ACROSS PARTS OF SOUTHERN/ EASTERN ALABAMA HAS LOWERED BOUNDARY LAYER DEW POINTS SOME. HOWEVER...MIXED LAYER CAPE UP TO 1000 J/KG IS STILL SUPPORTIVE OF VIGOROUS UPDRAFTS IN FAVORABLE SHEAR ENVIRONMENT ASSOCIATED WITH 40 TO 50 KT CYCLONIC MID-LEVEL FLOW. MOST SIGNIFICANT THUNDERSTORM ACTIVITY WILL PROGRESS THROUGH BIRMINGHAM SHORTLY...AND LIKELY MONTGOMERY BY 22-23Z...POSSIBLY APPROACHING THE ATLANTA METROPOLITAN AREA WITH POTENTIAL FOR HAIL AND DAMAGING WINDS BY 22/00Z. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...MOB... 31738815 32628837 33628714 34678430 33588378 32508417 31098546 30798673 30928818 WWWW From Mcd at goshenarc.org Fri Apr 21 21:00:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 17:00:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212058 SWOMCD SPC MCD 212057 CAZ000-212300- MESOSCALE DISCUSSION 0607 NWS STORM PREDICTION CENTER NORMAN OK 0357 PM CDT FRI APR 21 2006 AREAS AFFECTED...NORTHERN/CENTRAL CA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 212057Z - 212300Z THREAT FOR ISOLATED HAIL WILL INCREASE REMAINDER OF THE AFTERNOON ACROSS INTERIOR PORTIONS OF NORTHERN/CENTRAL CA. A WATCH IS NOT CURRENTLY ANTICIPATED...HOWEVER WILL CONTINUE TO MONITOR CONVECTIVE TRENDS. WATER VAPOR IMAGERY FEATURES UPPER LOW JUST OFF THE CENTRAL CA COAST. AS THIS LOW NEARS THE COAST...MID LEVEL LAPSE RATES WILL CONTINUE TO STEEPEN INTO INTERIOR CA. INITIAL THUNDERSTORM DEVELOPMENT IS ALREADY NOTED EAST OF THE BAY AREA...WITH INCREASING CONVECTIVE COVERAGE EXPECTED THROUGH LATE AFTERNOON FROM THE COASTAL AREAS INTO THE SACRAMENTO/SAN JOAQUIN VALLEYS. PROGRESSIVELY COOL TEMPERATURES ALOFT COUPLED WITH A MILD BOUNDARY LAYER AND UPPER 40S/LOWER 50S DEWPOINTS WILL LEAD TO POTENTIAL FOR MOST UNSTABLE CAPES IN EXCESS OF 1000 J/KG PER ADJUSTED RUC SOUNDINGS...ESPECIALLY IN AREAS FROM SACRAMENTO/STOCKTON AND SOUTH. PRIMARY SEVERE HAZARD IS LIKELY TO BE HAIL THROUGH EARLY EVENING...ALTHOUGH A FEW FUNNELS MAY BE POSSIBLE AS WELL. ..GUYER.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HNX...STO...MTR... 40482263 40562202 40142158 39442099 38172048 36791933 36461966 36372013 36902089 37822193 38772268 39342278 WWWW From Mcd at goshenarc.org Fri Apr 21 23:25:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 19:25:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212323 SWOMCD SPC MCD 212322 SCZ000-NCZ000-GAZ000-TNZ000-220045- MESOSCALE DISCUSSION 0608 NWS STORM PREDICTION CENTER NORMAN OK 0622 PM CDT FRI APR 21 2006 AREAS AFFECTED...WRN SC...WRN NC...FAR ERN TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 212322Z - 220045Z THE THUNDERSTORMS DEVELOPING ACROSS THE WRN CAROLINAS AND NERN GA WILL LIKELY MAINTAIN A SEVERE THREAT OVER THE NEXT FEW HOURS. LARGE HAIL AND WIND DAMAGE SHOULD BE THE PRIMARY THREATS. SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING NWD ACROSS ERN GA INTO WRN NC WHERE DEWPOINTS ARE IN THE LOWER 60S F. LOW-LEVEL CONVERGENCE ALONG THE MOIST AXIS AND SFC HEATING IS RESULTING IN THUNDERSTORM DEVELOPMENT. STORMS SHOULD REMAIN RELATIVELY ISOLATED THIS EVENING DUE TO A LACK OF LARGE-SCALE ASCENT ACROSS THE REGION ASSOCIATED WITH AN UPPER-LEVEL RIDGE. HOWEVER...FORECAST SOUNDINGS SHOW MODERATE INSTABILITY REMAINING IN PLACE THIS EVENING WITH STEEP LAPSE RATES AND SUFFICIENT SHEAR FOR A SEVERE THREAT WITH LARGE HAIL AND ISOLATED WIND DAMAGE. DUE TO THE WEAK ASCENT...THE ACTIVITY SHOULD DECREASE IN INTENSITY AFTER SUNSET AS SFC TEMPS COOL AND INSTABILITY DECREASES ACROSS THE REGION. ..BROYLES.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...CAE...GSP...MRX...FFC... 33148225 33348288 33808313 34578338 36178343 36218141 34908087 33358074 WWWW From Mcd at goshenarc.org Sat Apr 22 01:08:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 21:08:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220106 SWOMCD SPC MCD 220105 GAZ000-ALZ000-220300- MESOSCALE DISCUSSION 0609 NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT FRI APR 21 2006 AREAS AFFECTED...SE AL...GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 220105Z - 220300Z THE SEVERE THREAT OVER SE AL AND GA WILL LIKELY INCREASE THIS EVENING AS AN MCS MOVES ENEWD TOWARD THE ATLANTA AREA. ADDITIONAL STORMS SHOULD INTENSIFY ACROSS SE AL AND SHOULD MOVE INTO SW GA LATER THIS EVENING. A WW WILL BECOME NECESSARY BY 0130Z. WATER VAPOR IMAGERY CURRENTLY SHOWS A SHORTWAVE TROUGH MOVING ENEWD ACROSS AL ATTM. THUNDERSTORMS ARE DEVELOPING ALONG THE LEADING EDGE OF ASCENT AND WILL LIKELY INCREASE IN COVERAGE AS THE TROUGH MOVES ACROSS THE REGION. ALTHOUGH WSR-88D VWPS CURRENTLY SHOW 0-6 KM SHEAR VALUES OF 30 TO 35 KT...THE MODERATE INSTABILITY SHOULD BE ENOUGH FOR STRONG MULTICELL STORMS OR PERHAPS ISOLATED SUPERCELLS. STEEP LOW-LEVEL LAPSE RATES SHOWN ON FORECASTS SOUNDINGS WILL FAVOR WIND DAMAGE WITH THE STRONGER CELLS. IN ADDITION...THE SHEAR PROFILES AND MODERATE INSTABILITY MAY ALLOW A FEW SUPERCELL STORMS TO DEVELOP CAPABLE OF LARGE HAIL AND ISOLATED WIND DAMAGE. ..BROYLES.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...FFC...TAE...BMX...MOB... 31328422 31048503 31208593 31968640 32968604 33608527 34478414 34078292 33248274 WWWW From Mcd at goshenarc.org Sat Apr 22 03:42:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 23:42:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220340 SWOMCD SPC MCD 220340 FLZ000-GAZ000-ALZ000-MSZ000-220545- MESOSCALE DISCUSSION 0610 NWS STORM PREDICTION CENTER NORMAN OK 1040 PM CDT FRI APR 21 2006 AREAS AFFECTED...FL PANHANDLE...SRN AL...SE MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 220340Z - 220545Z AN ISOLATED TORNADO THREAT WILL EXIST WITH ROTATING CELLS OVER THE NEXT FEW HOURS ACROSS SRN AL AND THE FL PANHANDLE. A TORNADO WATCH WILL BE ISSUED SHORTLY. A LINE OF STORMS IS CURRENTLY INTENSIFYING ALONG THE GULF COAST OF AL AND THE FL PANHANDLE. THE CONVECTION IS JUST AHEAD OF AN APPROACHING SHORTWAVE TROUGH OVER THE LOWER MS VALLEY AND SHOULD INCREASE IN COVERAGE OVER THE NEXT FEW HOURS. FORECAST SOUNDINGS FOR THIS AREA TONIGHT INCREASE VERTICAL SHEAR AS A MID-LEVEL JET APPROACHES THE REGION. IN ADDITION...MODERATE INSTABILITY IS PRESENT WITH STRONG LOW-LEVEL SHEAR AS INDICATED BY REGIONAL WSR-88D VWPS. THIS SHOULD BE ADEQUATE FOR ROTATING STORMS WITH A TORNADO POTENTIAL. ALSO...ISOLATED WIND DAMAGE AND HAIL WILL BE POSSIBLE WITH THE STRONGER STORMS. ..BROYLES.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB...LIX... 30028708 29978863 30268892 30718898 31248871 31408855 31508754 31368603 31158502 30468489 30078536 29978692 WWWW From Mcd at goshenarc.org Sat Apr 22 07:30:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 03:30:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220728 SWOMCD SPC MCD 220728 GAZ000-ALZ000-220830- MESOSCALE DISCUSSION 0611 NWS STORM PREDICTION CENTER NORMAN OK 0228 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS ERN AL...GA. CONCERNING...SEVERE THUNDERSTORM WATCH 235... VALID 220728Z - 220830Z WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 8Z. MRGL/ISOLATED SEVERE HAIL OR STRONG GUSTS CAPABLE OF MINOR DAMAGE MAY STILL OCCUR FROM MOST VIGOROUS CONVECTION IN COMPLEX MOVING EWD FROM SERN AL OVER SRN GA. HOWEVER ORGANIZED SEVERE RISK DOES NOT APPEAR GREAT ENOUGH TO WARRANT ADDITIONAL WW ATTM. HOWEVER...EXPECT INCREASE IN POTENTIAL FOR GEN TSTMS OVER SRN GA NEXT FEW HOURS...AS PORTIONS OF TSTM COMPLEX NOW OVER SERN AL AND FL PANHANDLE MOVE ENEWD. CYCLONIC TURNING IN REFLECTIVITY ANIMATIONS INDICATES EMBEDDED MCV MOVING ENEWD 30-35 KT OVER AREA BETWEEN AUO-DHN AS OF 715Z...WHICH MAY ENHANCE INSTABILITY ALOFT...IN COMBINATION WITH WEAK/AMBIENT/MIDLEVEL ASCENT AHEAD OF SHORTWAVE TROUGH...INDICATED IN MOISTURE CHANNEL IMAGERY INVOF MS/AL BORDER. THIS MAY RESULT IN MUCAPES UP TO AROUND 1200 J/KG. FOREGOING BOUNDARY LAYER SHOULD CONTINUE TO COOL DIABATICALLY...ROOTING STRONGEST BUOYANCY ABOVE SFC INVOF MOIST/SWLY LLJ. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAX...FFC...TAE...BMX... 31048581 31628608 32078604 32778491 32828364 32108278 31248317 31068414 WWWW From Mcd at goshenarc.org Sat Apr 22 07:56:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 03:56:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220754 SWOMCD SPC MCD 220754 FLZ000-ALZ000-220930- MESOSCALE DISCUSSION 0612 NWS STORM PREDICTION CENTER NORMAN OK 0254 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS FL PANHANDLE...EXTREME SRN AL. CONCERNING...TORNADO WATCH 236... VALID 220754Z - 220930Z BUOYANCY AND VERTICAL SHEAR PROFILES SUITABLE FOR SUPERCELLS REMAIN ACROSS MOST OF WW AREA...HOWEVER ORIENTATION/STRUCTURE OF CONVECTION IS NOT PARTICULARLY FAVORABLE. CONTINUATION OF THIS TREND MAY COMPEL EARLY CANCELLATION OF SOME OR ALL THIS WW. WITH VPS RADAR DATA MISSING...WW IS NOT WELL SAMPLED FOR OBSERVATIONAL WINDS ALOFT. HOWEVER...MODIFIED RUC SOUNDINGS AND WIND TRENDS FROM SERN AL RADAR SUGGEST SLOWLY DIMINISHING VERTICAL SHEAR PROFILES...BUT WITH ENOUGH LOW LEVEL SPEED SHEAR REMAINING TO ENLARGE HODOGRAPHS...YIELDING 100-200 J/KG 0-1 KM SRH OVER PORTIONS WRN FL PANHANDLE. MLCAPES UP TOO 1500 J/KG ARE EVIDENT AS WELL...SUPPORTED BY UPPER 60S/LOW 70S F SFC DEW POINTS. BY CONTRAST...CONVECTIVE MODE HAS BECOME PROGRESSIVELY MORE DISORGANIZED AND LESS DISCRETE...WITH MAIN BAND OF ACTIVITY ORIENTED NEARLY PARALLEL TO DEEP-LAYER SHEAR AND MEAN FLOW VECTORS. WHEN ACCOUNTING FOR TRANSLATIONAL MCS MOTION...THIS APPEARS TO RESULT IN SLIGHTLY ANAFRONTAL REGIME ASSOCIATED WITH EFFECTIVE BOUNDARY...WHICH IS NOT CONDUCIVE TO REDEVELOPING DISCRETE MODE. ADDITIONAL DEVELOPMENT MAY MOVE INLAND FROM GULF OR OCCUR OVER ANTECEDENT WARM SECTOR...HOWEVER PROBABILITIES APPEAR LOW ATTM BECAUSE OF PRONOUNCED WEAKNESS IN SFC FLOW AND CONVERGENCE AHEAD OF MCS. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB... 29778867 30388776 30958657 30858517 30558479 29968452 29508508 29668569 29868687 29828789 WWWW From Mcd at goshenarc.org Sat Apr 22 10:38:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 06:38:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221036 SWOMCD SPC MCD 221035 NCZ000-VAZ000-221230- MESOSCALE DISCUSSION 0613 NWS STORM PREDICTION CENTER NORMAN OK 0535 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS CENTRAL/NRN NC...S-CENTRAL VA. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221035Z - 221230Z TSTM SQUALL LINE -- EXTENDING FROM NC/VA BORDER VICINITY MTV...THROUGH GSO AREA TO UNION COUNTY NC AS OF 1015Z -- SHOULD CONTINUE TO MOVE NEWD 35-45 KT TOWARD S-CENTRAL VA. OCCASIONAL GUSTS BELOW 50 KT SEVERE CRITERIA -- BUT CAPABLE OF DMG TO WEAK STRUCTURES AND TREES -- MAY CONTINUE ALONG WITH MARGINALLY SEVERE HAIL. ATTM...WW NOT EXPECTED. SFC MESOANALYSIS SHOWS DIFFUSE WARM FRONT FROM NERN WV SEWD ACROSS SERN VA...S OF WHICH SFC TEMPS SHOULD REMAIN LOW-MID 60S F FOR ANOTHER COUPLE HOURS BEFORE DIABATIC HEATING COMMENCES AND/OR CONVECTIVE BAND PASSES. MOISTURE CHANNEL IMAGERY INDICATES SOME LARGE SCALE ASCENT IS POSSIBLE FROM MID-UPPER LEVEL PERTURBATION THAT EVOLVED FROM MCV PRODUCED BY SE TX ACTIVITY 24 HOURS AGO. AHEAD OF THIS PERTURBATION...DEEP-LAYER WIND PROFILES SHOULD REMAIN NEARLY UNIDIRECTIONAL THROUGH BUOYANT LAYER...WITH ELEVATED MUCAPES AROUND 700-800 J/KG ROOTED JUST ABOVE SFC. OBSERVATION SITES OVER NRN SC AND WRN NC CROSSED BY THIS LINE HAVE MEASURED GUSTS IN 25-37 KT RANGE...LESS THAN TRANSLATIONAL SPEED OF SQUALL LINE ITSELF IN MOST AREAS. RELATIVELY STABLE LAYER NEAR SFC -- EVIDENT IN MODIFIED RUC SOUNDINGS -- SHOULD CONTINUE TO LIMIT STRENGTH AND AREAL EXTENT OF MOST INTENSE SFC WINDS WITH THIS ACTIVITY. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...RAH...RNK...GSP... 34908048 35578028 35887997 36327995 36578013 37457841 37287784 36607756 36457753 36017766 35177885 WWWW From Mcd at goshenarc.org Sat Apr 22 12:31:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 08:31:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221228 SWOMCD SPC MCD 221228 NCZ000-SCZ000-221400- MESOSCALE DISCUSSION 0614 NWS STORM PREDICTION CENTER NORMAN OK 0728 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN SC...S-CENTRAL/SERN NC. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221228Z - 221400Z AREA IS BEING MONITORED FOR POSSIBLE WW. SHORT/INTENSIFYING LINE OF TSTMS...LOCATED BETWEEN AGS-CAE AS OF 12Z -- IS EXPECTED TO MOVE NEWD APPROXIMATELY 40 KT...CROSSING CAE AREA BY 13Z AND REACHING AREA BETWEEN FLO AND NC BORDER IN 14Z-15Z TIME FRAME GIVEN MOTION SIMILAR TO PRESENT. THIS BAND OF TSTMS MAY EXPAND -- BACKBUILDING EWD INTO MORE UNSTABLE AIR MASS -- AS IT MOVES NEWD ACROSS DISCUSSION AREA. MAIN THREAT WILL BE DAMAGING GUSTS...ESPECIALLY IN ANOTHER 2-3 HOURS AS ACTIVITY BECOMES MORE SFC-BASED. OCCASIONAL/MARGINALLY SEVERE HAIL ALSO IS POSSIBLE. EXPECT RELATIVELY FAST FORWARD SPEEDS TO CONTINUE IN ORDER FOR ACTIVITY TO MAINTAIN AT LEAST 10-15 KT STORM-RELATIVE INFLOW JUST ABOVE SFC...GIVEN 30-35 KT 850 MB WINDS EVIDENT IN REGIONAL VWP. FOREGOING SFC AIR MASS IS EXPECTED TO DESTABILIZE WITH ONSET OF DIABATIC SFC HEATING...WITH ONLY 2-3 DEG F WARMING NECESSARY TO ENSURE SFC-BASED LIFTED PARCEL BASED ON SHORT-TERM RUC FCST SOUNDINGS. MLCAPES MAY RISE TO 1000-1500 J/KG. WEAK SFC FLOW WILL CONTRIBUTE TO ENHANCED LOW LEVEL SHEAR VALUES THROUGH 0-3 KM LAYER...YIELDING SRH 100-200 J/KG. CAP APPARENT IN 12Z MHX SOUNDING WEAKENS WITH WWD EXTENT...AND WITH PROXIMITY TO INCREASING LARGE SCALE ASCENT ASSOCIATED WITH SHORTWAVE TROUGH LIFTING ENEWD ACROSS GA ATTM. THEREFORE ADDITIONAL DEVELOPMENT ALSO IS POSSIBLE SEPARATE FROM AFOREMENTIONED CONVECTIVE BAND...OVER ERN CAROLINAS. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CHS...CAE...GSP... 33278146 34148173 35248041 35727930 35537865 34877799 33507909 33108034 WWWW From Mcd at goshenarc.org Sat Apr 22 16:23:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 12:23:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221620 SWOMCD SPC MCD 221620 FLZ000-221745- MESOSCALE DISCUSSION 0615 NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT SAT APR 22 2006 AREAS AFFECTED...PARTS OF NRN FL/NRN FL PEN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221620Z - 221745Z SEVERE POTENTIAL SEEMS LIKELY TO INCREASE ACROSS PARTS OF NORTHEASTERN FLORIDA EARLY THIS AFTERNOON. WW IS NOT CURRENTLY ANTICIPATED...DUE PRIMARILY TO RELATIVELY SHORT TIME DURATION AND SOMEWHAT LIMITED AREAL COVERAGE/MAGNITUDE OF EXPECTED THREAT. SOUTHERN BRANCH SHORT WAVE TROUGH HAS CONTRIBUTED TO MAINTENANCE OF SMALL CONVECTIVE CLUSTER ACROSS AND EAST OF THE FLORIDA BIG BEND REGION. STRONGEST UPDRAFTS ARE ALREADY FAIRLY VIGOROUS...AND SEEM LIKELY TO INTENSIFY FURTHER NEXT FEW HOURS AS ELIMINATION OF NEAR SURFACE RADIATIONAL INVERSION ALLOWS DEVELOPMENT OUT OF BOUNDARY LAYER WITH CAPE OF 1500 TO 2000 J/KG. EMBEDDED WITHIN MODERATELY SHEARED ENVIRONMENT BENEATH 30 TO 40 KT CYCLONIC WESTERLY MID-LEVEL FLOW...DEVELOPING STORMS MAY POSE RISK OF MARGINALLY SEVERE HAIL AS THEY APPROACH GAINESVILLE BY 18Z. ASSOCIATED SURFACE COLD POOL SHOULD STRENGTHEN AS WELL...AND MAY BE ACCOMPANIED BY WINDS WHICH COULD BRIEFLY APPROACH SEVERE LIMITS ALONG GUST FRONT AS IT SPREADS EAST OF GAINESVILLE INTO COASTAL AREAS SOUTH OF JACKSONVILLE THROUGH DAYTONA BEACH BY 20Z. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MLB...TBW...JAX...TAE... 30248282 30348217 30158153 29688124 28928109 28918181 29208249 29438305 29858278 WWWW From Mcd at goshenarc.org Sat Apr 22 17:10:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 13:10:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221707 SWOMCD SPC MCD 221707 NCZ000-VAZ000-SCZ000-GAZ000-221830- MESOSCALE DISCUSSION 0616 NWS STORM PREDICTION CENTER NORMAN OK 1207 PM CDT SAT APR 22 2006 AREAS AFFECTED...CNTRL AND ERN NC...PARTS OF ERN SC AND SE VA CONCERNING...SEVERE THUNDERSTORM WATCH 237... VALID 221707Z - 221830Z CONTINUE WW 237. ADDITIONAL WW IS NOT CURRENTLY ANTICIPATED... BUT CONVECTIVE TRENDS NEAR AND TO THE LEE OF THE SOUTHERN APPALACHIANS...ACROSS PARTS OF NORTHEASTERN GEORGIA/SOUTH CAROLINA...ARE BEING MONITORED. MOST SIGNIFICANT IMPULSE EMBEDDED WITHIN BROADER SCALE SOUTHERN BRANCH TROUGH APPEARS TO BE JUST NOW SHIFTING EAST OF THE SOUTHERN APPALACHIANS. HOWEVER...SEVERAL WEAKER IMPULSES HAVE ALREADY PROGRESSED THROUGH CYCLONIC FLOW EXTENDING DOWNSTREAM...THROUGH THE SOUTHERN AND MID ATLANTIC COAST STATES. THIS INCLUDES ONE WAVE/WIND SHIFT WHICH HAS BECOME FOCUS FOR NARROW INTENSIFYING LINE OF CONVECTION FROM MYRTLE BEACH THROUGH RALEIGH INTO SOUTH CENTRAL VIRGINIA. WEAK TO MODERATE INSTABILITY AHEAD OF THIS ACTIVITY WILL SUPPORT A CONTINUING HAIL THREAT IN STRONGER STORMS. AND...30 TO 40 KT MEAN FLOW WILL CONTRIBUTE TO MODERATE NORTHEASTERLY STORM MOTIONS AND ENHANCED RISK OF STRONG GUSTY SURFACE WINDS ACROSS EASTERN NORTH CAROLINA/SOUTHEAST VIRGINIA THROUGH 21-22Z. SCATTERED THUNDERSTORMS ARE BEGINNING TO INCREASE IN NUMBER UPSTREAM...BUT LACK OF STRONGER LOW-LEVEL FOCUS AND DESTABILIZATION IN WAKE OF DOWNSTREAM CONVECTION SEEMS LIKELY TO LIMIT SEVERE POTENTIAL. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CHS...CAE...GSP...JAX...FFC...TAE... 32787933 32438061 31968164 31528347 32178394 34008375 35198271 35458051 36597861 36847816 37427728 37437691 36117605 35467602 34257669 33417774 33227820 33137844 WWWW From Mcd at goshenarc.org Sat Apr 22 19:22:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 15:22:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221919 SWOMCD SPC MCD 221919 MIZ000-OHZ000-INZ000-222115- MESOSCALE DISCUSSION 0617 NWS STORM PREDICTION CENTER NORMAN OK 0219 PM CDT SAT APR 22 2006 AREAS AFFECTED...LWR MI...NW OH...NRN AND CNTRL IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221919Z - 222115Z A WW IS NOT ANTICIPATED IN THE NEAR TERM...BUT COULD BECOME NECESSARY LATER THIS AFTERNOON. TRENDS ARE BEING MONITORED. AREA OF STRONGER MID-LEVEL FORCING/COOLING IS CURRENTLY OVERSPREADING LOWER MICHIGAN ASSOCIATED WITH IMPULSE PIVOTING AROUND SOUTHEASTERN QUADRANT OF CLOSED UPPER LOW. THIS IS CONTRIBUTING TO WEAK DESTABILIZATION...AND ONGOING DEEPENING CONVECTIVE DEVELOPMENT TO THE NORTHEAST/EAST OF MUSKEGON. MIXED LAYER CAPE IS STILL ONLY ON THE ORDER OF 500 J/KG...BUT WITH FURTHER HEATING IN MODERATELY SHEARED ENVIRONMENT...POTENTIAL FOR HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS SHOULD INCREASE. MOST VIGOROUS THUNDERSTORM ACTIVITY APPEARS LIKELY TO DEVELOP SOUTHEASTWARD TOWARD THE DETROIT AREA THROUGH 21-22Z. THEREAFTER...MODELS SEEM TO SUGGEST STRONGER MID-LEVEL FORCING WILL BECOME REORIENTED FROM SOUTHERN MICHIGAN SOUTHWESTWARD THROUGH PARTS OF NORTHERN/CENTRAL INDIANA...AS A 70 KT 500 MB JET STREAK NOSES AROUND SOUTHWESTERN PERIPHERY OF CLOSED LOW. PRE-FRONTAL THERMAL RIDGE AXIS ACROSS THIS REGION WILL BECOME FOCUS FOR STRONGEST DESTABILIZATION...IN KINEMATIC ENVIRONMENT SUPPORTIVE OF UPDRAFT ROTATION. ISOLATED LOW TOPPED SUPERCELLS APPEARS POSSIBLE...WITH LARGE HAIL/DAMAGING WIND GUSTS PRIMARY THREATS. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CLE...ILN...DTX...APX...IWX...GRR...IND... 43788588 44388579 44628499 44198345 43148267 42108261 40618382 39228594 39538720 40338716 41648574 WWWW From Mcd at goshenarc.org Sat Apr 22 19:55:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 15:55:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221953 SWOMCD SPC MCD 221952 TXZ000-NMZ000-222145- MESOSCALE DISCUSSION 0618 NWS STORM PREDICTION CENTER NORMAN OK 0252 PM CDT SAT APR 22 2006 AREAS AFFECTED...EASTERN NM INTO WEST/SOUTHWEST TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221952Z - 222145Z LARGE HAIL/DAMAGING WIND POTENTIAL IS EXPECTED TO INCREASE REMAINDER OF THE AFTERNOON/EARLY EVENING ACROSS EASTERN NM INTO WEST TX. MONITORING FOR A POSSIBLE SEVERE THUNDERSTORM WATCH...POSSIBLY BY 21Z-22Z. VISIBLE SATELLITE IMAGERY FEATURES TOWERING CU DEVELOPING IN VICINITY NM/SOUTHWEST TX MOUNTAINS AT MID AFTERNOON...NAMELY NEAR ROSWELL/ARTESIA NM. EVEN IN PRESENCE OF AFTERNOON BOUNDARY LAYER MIXING...50S/LOWER 60S F SURFACE DEWPOINTS HAVE BEEN MAINTAINED ACROSS WEST TX INTO FAR SOUTHEAST NM WITHIN LOW LEVEL SOUTHEASTERLY UPSLOPE FLOW. CONVECTIVE INHIBITION WILL CONTINUE TO ERODE OVER THE NEXT SEVERAL HOURS ACROSS THE EASTERN NM/WEST TX PLAINS...WITH INCREASING THUNDERSTORM COVERAGE/SEVERE POTENTIAL SPREADING EASTWARD EARLY THIS EVENING. LATEST RUC SOUNDINGS SUGGEST POTENTIAL FOR 1500-2000 J/KG MLCAPE. TRENDS FROM THE TUCUMCARI/WHITE SANDS NM PROFILERS SUGGEST A DEEPENING/LOWERING OF RELATIVELY STRONGER MID LEVEL FLOW OVER THE PAST SEVERAL HOURS...WITH 35-40 KTS SOUTHWESTERLY WINDS COMMON IN THE MID LEVELS. COUPLED WITH THE DEGREE OF INSTABILITY/LOW LEVEL SOUTHEASTERLY TRAJECTORIES...IT APPEARS THAT SUFFICIENT VERTICAL SHEAR WILL BE SUPERIMPOSED ACROSS THE AMBIENT WARM SECTOR FOR SUPERCELLS AND/OR WELL ORGANIZED MULTICELL CLUSTERS. ACTIVITY IS LIKELY TO DEVELOP/EVOLVE INTO WEST/NORTHWEST TX THIS EVENING WITH A CONTINUED LARGE HAIL THREAT...WITH DAMAGING WIND POTENTIAL POSSIBLY INCREASING AS STORMS GROW UPSCALE. IT APPEARS A SEVERE TSTM WATCH MAY BE NEEDED BY THE 21Z-22Z TIMEFRAME. ..GUYER.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...AMA...MAF...ABQ...EPZ... 31520490 32570493 34550442 35810361 35850175 34910117 32710205 31000258 30970385 WWWW From Mcd at goshenarc.org Sat Apr 22 20:21:38 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 16:21:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222019 SWOMCD SPC MCD 222018 MOZ000-222215- MESOSCALE DISCUSSION 0619 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT SAT APR 22 2006 AREAS AFFECTED...MO OZARKS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 222018Z - 222215Z VIGOROUS CONVECTIVE DEVELOPMENT IS POSSIBLE BEFORE DARK. HOWEVER...IT SEEMS LIKELY THAT ANY SEVERE THREAT WILL BE FAIRLY LOCALIZED...AND A WW IS NOT CURRENTLY ANTICIPATED. AHEAD OF DEVELOPING COLD FRONT...ASSOCIATED WITH IMPULSE ROTATING AROUND SOUTHWESTERN PERIPHERY OF UPPER MISSISSIPPI VALLEY CLOSED LOW...LOW/MID-LEVEL WARM ADVECTION IS BECOMING MAXIMIZED NEAR THE MISSOURI OZARKS. THIS IS OCCURRING ON EASTERN FRINGE OF CAPPING LOW/MID-LEVEL PLAINS THERMAL RIDGE...WHERE MID-LEVEL LAPSE RATES ARE STEEP...AND CONTRIBUTING TO POTENTIAL INSTABILITY. LATEST OBJECTIVE ANALYSIS SUGGEST MIXED LAYER CAPE MAY INCREASE INTO THE 500 TO 1000 J/KG RANGE BY LATE AFTERNOON. MID-LEVEL SUBSIDENCE HAS SUPPRESSED CONVECTIVE DEVELOPMENT TO THIS POINT...BUT MODELS SUGGEST THIS WILL WEAKEN/SHIFT OFF TO THE EAST LATER THIS AFTERNOON AND EVENING. DEEPENING BOUNDARY LAYER BASED CUMULUS FIELD IS ALREADY EVIDENT ALONG THE MISSOURI/KANSAS BORDER TO THE NORTHEAST OF CHANUTE. IT APPEARS POSSIBLE THIS THAT ACTIVITY COULD CONTINUE TO DEVELOP INTO ISOLATED THUNDERSTORM ACTIVITY BEFORE 23/00Z. FRONTAL FORCING WILL ENHANCE LIFT FROM SOUTH CENTRAL MISSOURI THROUGH NORTH CENTRAL KANSAS...BUT CAP SEEMS LIKELY TO HOLD TO THE WEST OF THE MISSOURI/KANSAS BORDER. IF STORMS DEVELOP...SHEAR BENEATH 50+ KT NORTHWESTERLY MID-LEVEL FLOW WILL BE SUFFICIENT FOR SUPERCELLS...WITH ENHANCED RISK OF LARGE HAIL/DAMAGING WIND GUSTS. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX... 38419443 38679357 38559250 38469162 37899122 37399193 37369340 37799444 WWWW From Mcd at goshenarc.org Sat Apr 22 22:01:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 18:01:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222158 SWOMCD SPC MCD 222158 NCZ000-SCZ000-GAZ000-230000- MESOSCALE DISCUSSION 0620 NWS STORM PREDICTION CENTER NORMAN OK 0458 PM CDT SAT APR 22 2006 AREAS AFFECTED...SERN VA...ERN NC/SC....ERN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 222158Z - 230000Z ...NO ADDITIONAL WATCHES ARE CURRENTLY PLANNED FOR THE AREA... SEVERAL LINES/CLUSTERS OF STRONG STORMS SHOULD CONTINUE TO POSE A MARGINAL HAIL/WIND THREAT ACROSS PORTIONS OF EXTREME SERN VA...ERN NC AND SC...AND ERN GA FOR A COUPLE MORE HOURS. HOWEVER...LATEST DIAGNOSTIC DATA SUGGESTS MOIST/MARGINAL LAPSE RATES ACROSS THE REGION AFTER SEVERAL HOURS OF DEEP CONVECTION. WHILE A FEW POCKETS OF STRONGER INSTABILITY AND MODEST DEEP-LAYER FLOW PERSIST... DIMINISHING DIURNAL AND LARGE SCALE FORCING SHOULD RESULT IN A GRADUAL DECLINE IN STORM ORGANIZATION/INTENSITY. A FEW WEAKLY ORGANIZED MULTICELLULAR CLUSTERS REMAIN ONGOING WITH ATTENDANT THREAT OF SMALL HAIL...AND PERHAPS ONE OR TWO STRONG TO DAMAGING WIND GUSTS...BUT A NEW SEVERE TSTM WATCH DOES NOT APPEAR LIKELY AT THIS TIME. ..CARBIN.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CHS...CAE...JAX...FFC... 32128084 31558289 33638080 34628004 35957914 36157822 36017727 35697697 34927671 33897796 33467905 32518033 WWWW From Mcd at goshenarc.org Sat Apr 22 23:26:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 19:26:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222323 SWOMCD SPC MCD 222323 TXZ000-NMZ000-230130- MESOSCALE DISCUSSION 0621 NWS STORM PREDICTION CENTER NORMAN OK 0623 PM CDT SAT APR 22 2006 AREAS AFFECTED...EASTERN NM/WEST TX CONCERNING...SEVERE THUNDERSTORM WATCH 238... VALID 222323Z - 230130Z SEVERE THUNDERSTORM WATCH 238 CONTINUES UNTIL 03Z ACROSS FAR SOUTHEAST NM/SOUTHWEST TX. MONITORING FOR AN ADDITIONAL WATCH ISSUANCE TO THE NORTH/NORTHEAST OF WW 238 INTO WEST/NORTHWEST TX. AS OF 2315Z...SCATTERED STRONG STORMS ARE ONGOING ACROSS EAST CENTRAL/SOUTHEAST NM -- NAMELY ALONG HIGHWAY 285 CORRIDOR FROM SOUTHWEST OF TUCUMCARI TO NEAR ROSWELL/LOVINGTON -- INTO THE PECOS VALLEY/BIG BEND AREA OF SOUTHWEST TX. STORMS ARE LIKELY TO CONTINUE TO DEVELOP NORTHEASTWARD INTO FAR WEST/NORTHWEST TX THROUGH MID EVENING. LOW LEVEL MOISTURE INFLUX VIA SOUTHEASTERLY LOW LEVEL WINDS IS TENDING TO OFFSET VERTICAL MIXING...WITH PERSISTENCE OF LOWER/MIDDLE 50S F DEWPOINTS AS FAR NORTH AS THE LUBBOCK AREA PER THE WEST TX MESONET. LATEST TUCUMCARI PROFILER DATA SUPPORTS EFFECTIVE SHEAR OF 35-40 KTS...FAVORABLE FOR WELL ORGANIZED CLUSTERS/EMBEDDED SUPERCELLS. WHILE LARGE HAIL WILL LIKELY BE THE PRIMARY HAZARD...ONE OR MORE MCS CLUSTERS MAY EVOLVE INTO FAR WEST/NORTHWEST TX...WITH COLD POOL GENERATION/INCREASING SOUTHERLY LOW LEVEL JET POSSIBLY SUPPORTING SOME DAMAGING WIND THREAT AS WELL. ..GUYER.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...AMA...MAF...ABQ... 33780452 35370380 35580247 34880162 33490139 30940263 30580415 32180452 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 07:15:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 03:15:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230712 SWOMCD SPC MCD 230712 TXZ000-NMZ000-230945- MESOSCALE DISCUSSION 0625 NWS STORM PREDICTION CENTER NORMAN OK 0212 AM CDT SUN APR 23 2006 AREAS AFFECTED...PORTIONS W TX AND EXTREME SERN NM. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230712Z - 230945Z TSTMS ARE FORMING OVER PORTIONS PECOS VALLEY/PERMIAN BASIN REGIONS...FROM ERN CULBERSON COUNTY TX ENEWD ACROSS SERN CORNER OF NM. THIS ACTIVITY MAY INCREASE IN COVERAGE/INTENSITY AS IT MOVES ENEWD 15-20 KT ACROSS DISCUSSION AREA. OCCASIONAL HAIL IS POSSIBLE...HOWEVER SEVERE THREAT DOES NOT APPEAR SUFFICIENTLY ORGANIZED ATTM TO WARRANT WW. CONVENTIONAL SFC DATA AND W TX MESONET OBS INDICATE OUTFLOW BOUNDARY FROM EARLIER ACTIVITY EXTENDS FROM KENT COUNTY SWWD ACROSS MARTIN COUNTY TX...TO NEAR SERN TIP OF NM...BEFORE BECOMING DIFFUSE. AIR MASS ON BOTH SIDES OF BOUNDARY SHOULD CONTINUE GRADUAL DIABATIC COOLING...BENEATH 40-50 KT SSELY LLJ NOW EVIDENT IN MAF VWP AND JTN PROFILER. SUFFICIENT MOISTURE IS EVIDENT UPSTREAM TO SUPPORT CURRENT AND ADDITIONAL CONVECTIVE DEVELOPMENT OVER THIS REGION...BASED ON 00Z DRT RAOB AND 850 MB ANALYSIS. ACTIVITY SHOULD REMAIN ROOTED ABOVE SFC...WITH 8-9 DEG C/KM MIDLEVEL LAPSE RATES SUPPORTING ELEVATED MUCAPES AROUND 1000 J/KG ABOVE WRN PORTION OF OUTFLOW AIR MASS. CONVECTION SHOULD CONTINUE TO BECOME MORE DISORGANIZED WITH EWD EXTENT ACROSS SOUTH PLAINS/PERMIAN BASIN REGION. WEAK MIDLEVEL FLOW IN 500-700 MB LAYER WILL BE A LIMITING FACTOR FOR DEEP-LAYER SHEAR...RESULTING IN EFFECTIVE SHEARS IN 20-35 KT RANGE. ALSO...MODIFIED RUC SOUNDINGS SUGGEST INCREASING CINH FROM MAF/LBB LONGITUDE EWD. ..EDWARDS.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...MAF... 31300378 31500407 31920405 32230386 32650305 33000220 32790134 32330129 31430229 31120332 31150370 WWWW From Mcd at goshenarc.org Sun Apr 23 20:17:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 16:17:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232015 SWOMCD SPC MCD 232014 KSZ000-OKZ000-TXZ000-232215- MESOSCALE DISCUSSION 0626 NWS STORM PREDICTION CENTER NORMAN OK 0314 PM CDT SUN APR 23 2006 AREAS AFFECTED...WRN KS TO ERN TX PANHANDLE CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232014Z - 232215Z ...SEVERE THUNDERSTORM WATCH WILL BE REQUIRED FOR PORTIONS OF THE HIGH PLAINS OF KS...OK/TX PANHANDLE... BOUNDARY LAYER HAS WARMED RAPIDLY ACROSS THE CNTRL/SRN HIGH PLAINS...ESPECIALLY POST DRYLINE WHERE LOWEST 3KM LAPSE RATES ARE NEAR DRY ADIABATIC. IT APPEARS DRYLINE HAS MIXED AS FAR EAST AS IT WILL GO THIS AFTERNOON...WITH AN APPARENT NWWD MOISTURE SURGE NOW ADVECTING INTO THE ERN TX PANHANDLE AS PRESSURE FALLS FOCUS IN THE LEE OF THE SRN CO ROCKIES. STEEP LAPSE RATE ENVIRONMENT HAS AIDED HIGH BASED CONVECTION WITH ISOLATED LIGHTNING OVER SERN CO/SWRN KS...WHICH IS SPREADING NEWD AT ROUGHLY 40KT. THIS SPEED WOULD ALLOW DEEP CONVECTION/BOUNDARY LAYER MOISTURE INTERSECTION BY 21Z. ADDITIONALLY...BOUNDARY LAYER CU IS DEVELOPING RAPIDLY ALONG DRYLINE ACROSS THE TX PANHANDLE. IT APPEARS SIGNIFICANT THUNDERSTORM DEVELOPMENT WILL OCCUR ACROSS THIS REGION OVER THE NEXT FEW HOURS AND SEVERE THUNDERSTORM WATCH WILL BE ISSUED SOON. ..DARROW.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...GID...DDC...GLD...AMA... 34830182 36570138 37800086 39520128 39419944 35450020 WWWW From Mcd at goshenarc.org Sun Apr 23 22:15:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 18:15:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232212 SWOMCD SPC MCD 232212 MOZ000-KSZ000-232345- MESOSCALE DISCUSSION 0627 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...SWRN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232212Z - 232345Z ERN KS AND SWRN MO CONTINUE TO BE MONITORED FOR POTENTIALLY RAPID SEVERE TSTM DEVELOPMENT THIS EVENING. WARM FRONT...REINFORCED BY CONVECTIVE OUTFLOW ACROSS SWRN MO...APPEARS IN LATEST MESOANALYSIS NORTH OF A SLN-EMP-JLN LINE. PERSISTENT MESOSCALE FORCING NEAR THE BOUNDARY...COUPLED WITH STRONG HEATING AND MOISTENING ACROSS THE WARM SECTOR...ARE EXPECTED TO RESULT IN TSTM INITIATION THIS EVENING. LARGE SCALE LIFT BENEATH UPPER RIDGE...WHILE NOT CURRENTLY SIGNIFICANT...MAY BE ENHANCED BY APPROACH OF MID/UPPER LEVEL DISTURBANCE CRESTING THE RIDGE AXIS ACROSS NWRN KS ATTM. NOCTURNAL INCREASE IN LOW LEVEL JET ACROSS THE FRONT WILL ALSO INCREASE TSTM DEVELOPMENT POTENTIAL. AIR MASS BEING TRANSPORTED INTO THE ZONE OF FORCING IS VERY UNSTABLE AND SHOULD FUEL INTENSE UPDRAFTS. LATEST MODEL GUIDANCE APPEARS TO SUPPORT STORM DEVELOPMENT ACROSS THE AREA IN THE 00Z-03Z TIME FRAME WITH THE STRONGEST VERTICAL MOTION OCCURRING NORTH OF THE SURFACE BOUNDARY. GENERALLY WEAK LOW LEVEL FLOW TOPPED BY MODEST WLY FLOW OF 40-50KT IN THE MID LEVELS WILL RESULT IN SUFFICIENT SHEAR FOR STORM ROTATION. SHEAR NEAR THE BOUNDARY WILL LIKELY STRENGTHEN THIS EVENING AS LOW LEVEL FLOW INCREASES AND STORM INTERACTIONS LOCALLY REINFORCE HORIZONTAL THERMAL GRADIENTS. SEVERE HAIL AND WIND APPEAR POSSIBLE AND A TORNADO OR TWO CANNOT BE RULED FROM ANY CELL TRACKING NEAR THE FRONT THIS EVENING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT... 38149294 36919331 37339741 38869763 39519684 39149403 38799317 WWWW From Mcd at goshenarc.org Sun Apr 23 23:49:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 19:49:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232347 SWOMCD SPC MCD 232346 TXZ000-240115- MESOSCALE DISCUSSION 0628 NWS STORM PREDICTION CENTER NORMAN OK 0646 PM CDT SUN APR 23 2006 AREAS AFFECTED...TX SOUTH PLAINS/CAPROCK VICINITY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232346Z - 240115Z ALTHOUGH CONVECTIVE INITIATION REMAINS UNCERTAIN...A CONDITIONAL THREAT FOR LARGE HAIL/DAMAGING WINDS EXISTS GIVEN THUNDERSTORM DEVELOPMENT EARLY THIS EVENING ACROSS THE TX SOUTH PLAINS/CAPROCK VICINITY. A WATCH IS NOT CURRENTLY ANTICIPATED. VISIBLE SATELLITE OVER THE PAST FEW HOURS PORTRAYS MODEST CU FIELD/FAILED ATTEMPTS AT CONVECTIVE INITIATION NEAR THE LUBBOCK VICINITY LATE THIS AFTERNOON. WHILE MASS FIELDS ARE BETTER FOCUSED TO THE NORTH/EAST OF THE REGION...SUFFICIENT HEATING/MIXING IN VICINITY OF THE DRYLINE HAS LARGELY ERODED THE CONVECTIVE INHIBITION ACROSS THE TX SOUTH PLAINS/CAPROCK VICINITY PER ADJUSTED RUC SOUNDINGS/18Z REESE RAOB. IN PRESENCE OF MODEST MASS CONVERGENCE...SOME WINDOW FOR THUNDERSTORM DEVELOPMENT YET REMAINS OVER THE NEXT FEW HOURS ACROSS WEST TX. GIVEN INITIATION...COMBINATION OF MODERATE INSTABILITY/MODEST VERTICAL SHEAR OF 25-30 KTS WOULD SUPPORT AT LEAST A SHORT-LIVED SEVERE THREAT...WITH LARGE HAIL/DAMAGING WIND POTENTIAL. EVEN PROVIDED CONVECTIVE INITIATION...CURRENT EXPECTATIONS ARE THAT DEVELOPMENT WOULD REMAIN SUFFICIENTLY ISOLATED TO PRECLUDE A WATCH ISSUANCE. ..GUYER.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...MAF... 34260284 34560161 34280043 32610079 32850264 WWWW From Mcd at goshenarc.org Mon Apr 24 00:12:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 20:12:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240010 SWOMCD SPC MCD 240009 KSZ000-COZ000-240145- MESOSCALE DISCUSSION 0629 NWS STORM PREDICTION CENTER NORMAN OK 0709 PM CDT SUN APR 23 2006 AREAS AFFECTED...NERN CO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240009Z - 240145Z TSTMS WITH HAIL MAY INCREASE FROM THE FRONT RANGE ENEWD ACROSS NERN CO THIS EVENING. STRONG FRONTAL SURGE AND DEEPENING UPSLOPE FLOW WILL COMBINE WITH POST FRONTAL MOISTURE AND INSTABILITY TO FUEL A FEW STRONG TO SEVERE STORMS ACROSS THE REGION TONIGHT. INITIATION ON THE FRONT RANGE HAS BEGUN WITH HAIL RECENTLY REPORTED IN THE DENVER AREA. GIVEN STRENGTHENING LARGE SCALE ASCENT ASSOCIATED WITH THE APPROACH OF FOUR CORNERS SHORT WAVE TROUGH...AND PRESENCE OF DEVELOPING LEE-SIDE CYCLONE AND SURFACE FRONT EXTENDING EWD INTO NWRN KS...FEATURES APPEAR IN PLACE TO SUPPORT ADDITIONAL TSTM DEVELOPMENT ACROSS THE REGION. STRONG DIRECTIONAL AND SPEED SHEAR WITHIN THE CLOUD-BEARING LAYER WILL FURTHER PROMOTE STORM INTENSITY WITH HAIL APPEARING TO BE THE PRIMARY THREAT. AREA WILL CONTINUE TO BE MONITORED FOR INCREASING STORM COVERAGE BUT A WATCH DOES NOT APPEAR IMMINENT. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GLD...PUB...BOU... 39050316 38890428 38940503 39200523 39600527 40180497 40560425 40750370 40810322 40740290 40640268 40510233 40210214 39920209 39640204 39320203 WWWW From Mcd at goshenarc.org Mon Apr 24 01:01:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 21:01:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240058 SWOMCD SPC MCD 240058 MOZ000-KSZ000-240230- MESOSCALE DISCUSSION 0630 NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...WRN MO CONCERNING...SEVERE THUNDERSTORM WATCH 240... VALID 240058Z - 240230Z ISOLATED CELLS HAVE RECENTLY DEVELOPED ALONG QUASI-STATIONARY BOUNDARY FROM NERN KS INTO WRN MO. BASED ON LATEST SOUNDING INFORMATION FROM SGF AND TOP...MODIFIED FOR ESTIMATED ENVIRONMENTAL CONDITIONS NEAR THE FRONT...ISOLATED TORNADO POTENTIAL MAY BE INCREASING. RECENT DISCRETE STORM DEVELOPMENT ON THE FRONT IN OTTAWA AND MORRIS COUNTIES HAS OCCURRED ON THE SYNOPTIC FRONT WHERE SOUNDING AND PROFILER DATA SUGGEST STORM RELATIVE HELICITY (SRH) MAY BE QUITE HIGH. BASED ON PROXIMITY RAOB AND PROFILER DATA...0-1KM SRH WAS CURRENTLY ESTIMATED AT OVER 150 M2/S2...WHILE 0-3KM SRH MAY BE AS HIGH AS 400 M2/S2 FOR 300/12KT CELL MOTION. IN ADDITION TO RELATIVELY LOW LFC OF AROUND 1-2KM NEAR THE BOUNDARY THIS WOULD SUPPORT THE POTENTIAL FOR STRONG LOW LEVEL STORM ROTATION AND PERHAPS TORNADO FORMATION FOR UPDRAFTS REMAINING NEAR THE FRONTAL ZONE OVER THE NEXT HOUR OR SO. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 02:28:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 22:28:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240226 SWOMCD SPC MCD 240226 MOZ000-KSZ000-240330- MESOSCALE DISCUSSION 0631 NWS STORM PREDICTION CENTER NORMAN OK 0926 PM CDT SUN APR 23 2006 AREAS AFFECTED...TX/OK PNHDLS...NWRN OK...WRN KS CONCERNING...SEVERE THUNDERSTORM WATCH 239... VALID 240226Z - 240330Z TSTM COVERAGE AND INTENSITY WAS DECREASING ACROSS SEVERE TSTM WATCH 239 AT THIS HOUR. DRY LINE WAS RETREATING NWWD ACROSS THE WRN PORTIONS OF THE PNHDLS AS LEE-SIDE LOW GRADUALLY STRENGTHENS OVER SERN CO. LATEST RUC AND SREF GUIDANCE INDICATED THE THREAT FOR ORGANIZED SEVERE STORMS WITHIN WATCH 239 REGION SHOULD REMAIN LOW FOR THE REMAINDER OF THE NIGHT AND NO ADDITIONAL WATCHES ARE ANTICIPATED IN THIS AREA. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 02:50:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 22:50:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240247 SWOMCD SPC MCD 240247 MOZ000-KSZ000-240415- MESOSCALE DISCUSSION 0632 NWS STORM PREDICTION CENTER NORMAN OK 0947 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...WRN MO CONCERNING...SEVERE THUNDERSTORM WATCH 240... VALID 240247Z - 240415Z ...LARGE AND POTENTIALLY DANGEROUS MCS HAS EVOLVED ACROSS SERN KS... EXPECT LINEAR MCS WITH MESOCYCLONIC COMMA-HEAD COMPLEX TO CONTINUE MOVING EAST AT UP TO 50KT ACROSS SERN KS OVER THE NEXT COUPLE OF HOURS. STRONG TO DAMAGING WIND GUSTS AND VERY LARGE HAIL SHOULD ACCOMPANY THIS SYSTEM ACROSS LYON...COFFEY...GREENWOOD...AND WOODSON COUNTIES OVER THE NEXT HOUR AND A HALF. ACTIVITY MAY THEN MERGE WITH OTHER INTENSE STORMS FORMING NEAR STATIONARY WARM FRONT FROM ALLEN AND ANDERSON COUNTIES IN EXTREME SERN KS...TO VERNON...ST. CLAIR...CEDAR...AND HICKORY COUNTIES IN WRN MO. ANOTHER INTENSE RIGHT-MOVING SUPERCELL STORM WAS CROSSING THE LAWRENCE KS AREA. IN ADDITION TO TORNADO POTENTIAL AND DAMAGING WINDS FROM THIS CELL... VERY LARGE AND DAMAGING HAIL WILL ALSO BE POSSIBLE. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 03:15:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 23:15:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240310 SWOMCD SPC MCD 240310 KSZ000-NEZ000-COZ000-240445- MESOSCALE DISCUSSION 0633 NWS STORM PREDICTION CENTER NORMAN OK 1010 PM CDT SUN APR 23 2006 AREAS AFFECTED...NERN CO...WRN NEB...NWRN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240310Z - 240445Z THREAT FOR ELEVATED SUPERCELLS WITH LARGE HAIL APPEARS TO BE INCREASING ACROSS NERN CO THIS EVENING. DYNAMICS AND INSTABILITY SHOULD SUPPORT THE EVOLUTION OF A SMALL MCS ACROSS THE NWRN KS/SWRN NEB BORDER AREA OVER THE NEXT FEW HOURS. A WATCH WILL BE ISSUED SHORTLY. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GID...LBF...GLD...BOU... 39100023 39670288 41040228 40469964  From Mcd at goshenarc.org Mon Apr 24 06:30:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 02:30:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240627 SWOMCD SPC MCD 240627 KSZ000-OKZ000-240830- MESOSCALE DISCUSSION 0634 NWS STORM PREDICTION CENTER NORMAN OK 0127 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/SERN KS...N-CENTRAL-NERN OK. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240627Z - 240830Z TSTMS MAY CONTINUE TO INCREASE IN COVERAGE ON BOTH SIDES OF KS/OK BORDER...N OF OUTFLOW BOUNDARY LEFT BEHIND BY MCS THAT NOW IS DECAYING OVER SRN MO. MAIN THREAT SHOULD BE LARGE HAIL. GUST POTENTIAL BECOMES LARGER WITH SWD EXTENT THROUGH DISCUSSION AREA...AND PROXIMITY TO OUTFLOW BOUNDARY. 61 KT GUST WAS MEASURED IN WOODWARD COUNTY OK AT 540Z. 6Z SFC ANALYSIS INDICATES OUTFLOW BOUNDARY FROM SERN DELAWARE COUNTY OK SWWD TO LINCOLN COUNTY...THEN NWWD ACROSS LOGAN/GARFIELD COUNTIES TO VICINITY NRN MAJOR/EXTREME SERN WOODS COUNTY. BOUNDARY WILL CONTINUE TO MOVE SEWD ACROSS NERN OK THROUGH AT LEAST 8Z. HOWEVER...IT SHOULD STALL SOON FROM LINCOLN COUNTY NWWD TO NEAR END...AND ALREADY HAS BECOME NEARLY STATIONARY FARTHER W. BAND OF TSTMS IS BECOMING BETTER ORGANIZED FROM PORTIONS PRATT COUNTY KS SWD TO WRN MAJOR COUNTY OK AND SHOULD CONTINUE MOVING EWD ALONG BOTH SIDES KS/OK BORDER. ANOTHER BAND OF CONVECTION IS EVIDENT FROM STAFFORD COUNTY KS SEWD TO KAY COUNTY OK...IN ZONE OF 850 MB WIND SHIFT AND APPARENT ISENTROPIC ASCENT MAX. MOST ACTIVITY SHOULD REMAIN ALONG AND N OF OUTFLOW BOUNDARY...IN REGIME OF ELEVATED LOW LEVEL WAA AIDED BY 40-50 KT LLJ EVIDENT IN VWP DATA. MODIFIED RUC SOUNDINGS INDICATE MIDLEVEL LAPSE RATES APCHG 9 DEG C/KM...ALONG WITH 850 MB DEW POINTS 13.5-15 DEG C...SUPPORTING ELEVATED MUCAPES 2000-3000 J/KG ROOTED AT TOP OF OUTFLOW AIR...WHICH DEEPENS WITH NWD EXTENT. 30-40 KT EFFECTIVE SHEAR PROFILES SHOULD AID IN STORM ORGANIZATION...MAINLY MULTICELLULAR IN CHARACTER. STRONG CINH EVIDENT S OF OUTFLOW AIR MASS SHOULD PRECLUDE SIGNIFICANT SWD PROPAGATION/BACKBUILDING OF THIS ACTIVITY. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...TOP...ICT...OUN...DDC... 36119939 36709876 37319883 38249896 38399866 38339652 38069545 37599495 36769520 36259635 36199874 WWWW From Mcd at goshenarc.org Mon Apr 24 07:08:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 03:08:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240705 SWOMCD SPC MCD 240705 KSZ000-NEZ000-COZ000-240830- MESOSCALE DISCUSSION 0635 NWS STORM PREDICTION CENTER NORMAN OK 0205 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS NWRN KS...NERN CO...SWRN NEB. CONCERNING...SEVERE THUNDERSTORM WATCH 241... VALID 240705Z - 240830Z SFC MESOANALYSIS SHOWS PRIMARY LOW OVER SERN CO...SE OF STRONG BARRIER-FLOW SURGE OF RELATIVELY COLD/STABLE SFC AIR. FALLING PRESSURES IN LEE-SIDE COLD SURGE INDICATE IT SHOULD WEAKEN OVER NEXT FEW HOURS...HOWEVER ASSOCIATED BAROCLINICITY IS EVIDENT FROM SFC LOW NNEWD INTO WEAKENING CONVECTIVE CLUSTER OVER SWRN NEB. UPSTREAM 850 MB FLOW IS VEERING WITH EMPHASIS SHIFTING TOWARD MORE FAVORABLE ASCENT FOR CONVECTION ACROSS CENTRAL NEB. PER COORDINATION W/LBF...CHASE/HAYES/FRONTIER COUNTIES ARE BEING CLEARED FROM WW. GIVEN CURRENT TRENDS AND DIMINISHING PROBABILITIES FOR ADDITIONAL DEVELOPMENT ELSEWHERE WITHIN ORIGINAL WW...REMAINING PORTIONS WW MAY BE CANCELLED AND/OR ALLOWED TO EXPIRE AS SCHEDULED AT 9Z. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GID...LBF...DDC...GLD... 39409960 38950035 38780174 39040233 40350207 40850109 40799982 40479942 WWWW From Mcd at goshenarc.org Mon Apr 24 12:34:56 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 08:34:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241232 SWOMCD SPC MCD 241232 KSZ000-OKZ000-241400- MESOSCALE DISCUSSION 0636 NWS STORM PREDICTION CENTER NORMAN OK 0732 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS N-CENTRAL/NERN OK...S-CENTRAL/SERN KS. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 241232Z - 241400Z LARGE HAIL POTENTIAL HAS INCREASED ONCE AGAIN ACROSS KS/OK BORDER REGION...AND MAY PROPAGATE SWD TOWARD I-35 CORRIDOR N OF OKC GIVEN CONVECTIVE TRENDS. AREA IS BEING MONITORED FOR POSSIBLE WW. SFC MESOANALYSIS SHOWS OLD OUTFLOW BOUNDARY FROM NEAR FSM WNWWD THROUGH LOGAN...KINGFISHER...WOODWARD COUNTIES OK...DRIFTING NWD W OF I-35. REINFORCING OUTFLOW AIR EXTENDS FROM NERN OK/NWRN AR CONVECTION WNWWD ACROSS PORTIONS SRN OSAGE COUNTY TO GRANT COUNTY...WITH WHICH ONE STORM IS INTERACTING AND SHOWING SOME EVIDENCE OF ROTATION ALOFT. OTHER TSTMS HAVE DEVELOPED RAPIDLY FROM ICT AREA SSWWD THROUGH KINGFISHER COUNTY OK. IR IMAGERY AND REFLECTIVITY DATA INDICATE LINE MAY SOLIDIFY SSWWD INTO CANADIAN COUNTY. THIS ACTIVITY SHOULD CONTINUE TO MOVE EWD ACROSS N-CENTRAL OK AND S-CENTRAL KS...WITH FAVORABLE VERTICAL SHEAR PROFILES FOR STORM ROTATION AND ENHANCED LARGE HAIL POTENTIAL. 35-50 KT EFFECTIVE SHEAR IS EVIDENT...DEPENDING ON CHOSEN LIFTED LAYER...WITH PARCELS LIKELY ROOTED AROUND 850 MB. FAVORABLE THERMODYNAMIC ENVIRONMENT OF ELEVATED WAA AND STEEP MIDLEVEL LAPSE RATES NEAR 9 DEG C/KM...YIELDS ELEVATED MUCAPES 1500-2500 J/KG...BASED ON MODIFIED RAOB DATA AND RUC FCST SOUNDINGS. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...TOP...ICT...OUN... 35879803 36689762 37499742 38029749 38249658 38249602 38109526 37769501 36829516 35599656 35689766 WWWW From Mcd at goshenarc.org Mon Apr 24 16:11:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 12:11:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241609 SWOMCD SPC MCD 241608 OKZ000-KSZ000-241745- MESOSCALE DISCUSSION 0637 NWS STORM PREDICTION CENTER NORMAN OK 1108 AM CDT MON APR 24 2006 AREAS AFFECTED...EXTREME SERN KS INTO NERN OK CONCERNING...SEVERE THUNDERSTORM WATCH 242... VALID 241608Z - 241745Z THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL MAY PERSIST ANOTHER COUPLE HOURS OR SO ACROSS NERN OK AS STORMS DEVELOP SLOWLY SWD. EARLY THIS MORNING A CLUSTER OF STORMS CONTINUES OVER NERN OK INTO SERN KS N OF A CONVECTIVE OUTFLOW BOUNDARY THAT CURRENTLY EXTENDS FROM CNTRL OK NWWD INTO NWRN OK. THE LOW LEVEL JET THAT CONTRIBUTED TO STRONG LIFT N OF THE OUTFLOW BOUNDARY HAS WEAKENED CONSIDERABLY OVER THE LAST FEW HOURS...AND MOST OF THE DISCRETE STORMS HAVE DISSIPATED. PRIMARY CONVECTIVE MODE HAS TRANSITIONED TO A CLUSTER OF STORMS OVER NERN OK THAT APPEARS TO BE PROPAGATING SWD ALONG THE CONVECTIVELY ENHANCED OUTFLOW BOUNDARY. NEW CELLS ARE ALSO DEVELOPING ALONG THE SWRN FLANKS OF THE CONVECTION AT THE INTERSECTION OF TWO OUTFLOW BOUNDARIES. THE ATMOSPHERE SW OF THIS ACTIVITY IS MODERATELY UNSTABLE WITH MLCAPE AROUND 2000 J/KG. THE LATEST OBJECTIVE ANALYSIS STILL SHOWS FAIRLY STRONG SURFACE BASED CONVECTIVE INHIBITION AND RAISES UNCERTAINTY HOW LONG THE STORMS WILL PERSIST. HOWEVER...AS THE BOUNDARY LAYER CONTINUES TO WARM AND THE CAP WEAKENS...STORMS ON THE SWRN FLANKS OF THIS ACTIVITY MAY CONTINUE TO DEVELOP SWD NEXT COUPLE HOURS. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN... 35759685 36619774 37149691 37149529 36059510 WWWW From Mcd at goshenarc.org Mon Apr 24 18:16:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 14:16:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241813 SWOMCD SPC MCD 241813 OKZ000-KSZ000-242015- MESOSCALE DISCUSSION 0638 NWS STORM PREDICTION CENTER NORMAN OK 0113 PM CDT MON APR 24 2006 AREAS AFFECTED...W CNTRL THROUGH NWRN OK INTO SWRN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 241813Z - 242015Z THUNDERSTORMS ARE EXPECTED TO DEVELOP IN A CORRIDOR FROM SWRN KS SWD INTO W CNTRL AND POSSIBLY SWRN OK BY MID AFTERNOON. SUPERCELLS WITH VERY LARGE HAIL AND A FEW TORNADOES WILL BE THE PRIMARY THREATS. TORNADO WATCH WILL LIKELY BE ISSUED WITHIN THE NEXT HOUR OR TWO. AN OUTFLOW BOUNDARY EXTENDS FROM NERN OK WWD TO A SURFACE LOW IN NWRN OK. ANOTHER MORE SUBTLE OUTFLOW BOUNDARY EXTENDS FROM E CNTRL OK NWWD INTO NWRN OK. A DRY LINE EXTENDS SWD FROM THE LOW THROUGH EXTREME WRN OK INTO NWRN TX. A COLD FRONT EXTENDS FROM NERN KS SWWD THROUGH SWRN KS AND FROM THE SURFACE LOW IN NWRN OK SWWD THROUGH THE TX PANHANDLE. THE ATMOSPHERE S OF THESE BOUNDARIES IS BECOMING VERY UNSTABLE. AMPLE SURFACE HEATING...RICH LOW LEVEL MOISTURE AND MID LEVEL LAPSE RATES AROUND 8.5 C/KM WILL SUPPORT MLCAPE FROM 3000 TO 3500 J/KG THIS AFTERNOON. A MID LEVEL JET MAX WILL ROTATE THROUGH THE BASE OF A SHORTWAVE TROUGH NOW OVER THE SRN ROCKIES NEWD INTO THE SRN AND CNTRL PLAINS THIS AFTERNOON AND EVENING WITH ATTENDANT HEIGHT FALLS. AS THIS OCCURS...THE SURFACE LOW IS FORECAST TO BECOME FOCUSED A LITTLE FARTHER SWD ACROSS W CNTRL OR SWRN OK LATER THIS AFTERNOON. THIS SUGGESTS THE LOW LEVEL FLOW SHOULD REMAIN BACKED TO SLY OVER CNTRL AND W CNTRL OK AHEAD OF THE DRYLINE. RECENT VWP DATA HAS SHOWN THE FLOW IN THE 1 TO 2 KM LAYER HAS BACKED DURING THE PAST HOUR ACROSS CNTRL OK. VISIBLE IMAGERY SHOWS CUMULUS INCREASING FROM NEAR THE TRIPLE POINT IN NWRN OK SWD THROUGH WRN OK ALONG AND E OF THE DRYLINE. STORMS ARE EXPECTED TO DEVELOP IN VICINITY OF THE TRIPLE POINT OVER NWRN OK AND SWRN KS AND SWD SOME DISTANCE ALONG THE DRYLINE WITHIN THE NEXT 2-3 HOURS AS THE CAP CONTINUES TO WEAKEN. DEEP LAYER SHEAR WILL INCREASE AND BECOME SUPPORTIVE OF SUPERCELLS AS THE MID LEVEL SPEED MAX ADVANCES EWD. GIVEN THE VERY FAVORABLE THERMODYNAMIC PROFILES AND LIKELIHOOD FOR SUPERCELLS...VERY LARGE HAIL WILL BE LIKELY. BEST TORNADO THREAT APPEARS TO BE ACROSS PARTS OF NWRN AND CNTRL OK INTO SWRN KS WHERE STORMS WILL HAVE THE OPPORTUNITY TO INTERACT WITH MODIFYING OUTFLOW BOUNDARIES. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ICT...OUN...DDC... 34919704 34509864 35769893 37059962 37419964 37489874 36539756 35749685 WWWW From Mcd at goshenarc.org Mon Apr 24 19:17:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 15:17:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241914 SWOMCD SPC MCD 241914 ARZ000-MOZ000-OKZ000-242015- MESOSCALE DISCUSSION 0639 NWS STORM PREDICTION CENTER NORMAN OK 0214 PM CDT MON APR 24 2006 AREAS AFFECTED...ERN OK THROUGH NRN AND CNTRL AR CONCERNING...SEVERE THUNDERSTORM WATCH 243... VALID 241914Z - 242015Z STORMS ARE EXPECTED TO CONTINUE DEVELOPING SEWD THROUGH ERN OK INTO NRN AND CNTRL AR NEXT FEW HOURS. LARGE HAIL AND ISOLATED DAMAGING WIND WILL BE THE PRIMARY THREATS. A NEW WW WILL LIKELY BE NEEDED FOR PORTIONS OF ERN OK INTO WRN AR WITHIN THE NEXT HOUR OR SO. THIS AFTERNOON A LINE OF SEVERE STORMS FROM NERN OK INTO NWRN AR CONTINUES SEWD. THE LINE HAS TRANSITIONED TO A FORWARD PROPAGATING MCS...AND THE ATMOSPHERE DOWNSTREAM ACROSS NWRN AR AND ERN OK HAS BECOME MODERATELY UNSTABLE WITH MLCAPE FROM 2000 TO 2500 J/KG. LOW LEVEL CONVERGENCE AND LIFT ALONG THE GUST FRONT ALONG WITH WEAKENING CONVECTIVE INHIBITION SHOULD SUSTAIN THE MCS THROUGH ERN OK NRN AR NEXT FEW HOURS. STEEP MID LEVEL LAPSE RATES...STRONG INSTABILITY AND SUFFICIENT CLOUD LAYER SHEAR FOR EMBEDDED SUPERCELLS WILL CONTINUE TO SUPPORT A THREAT FOR LARGE HAIL. ISOLATED DAMAGING WIND GUSTS MAY ALSO ACCOMPANY THE STRONGER STORMS. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF...TSA... 35849585 36519407 36319102 34579194 34799514 WWWW From Mcd at goshenarc.org Mon Apr 24 20:21:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 16:21:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242018 SWOMCD SPC MCD 242018 MOZ000-KSZ000-NEZ000-242215- MESOSCALE DISCUSSION 0641 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/EASTERN KS INTO FAR WESTERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242018Z - 242215Z SEVERE POTENTIAL /WITH PRIMARY HAZARD OF LARGE HAIL/ IS EXPECTED TO INCREASE OVER THE NEXT FEW HOURS ACROSS NORTH CENTRAL/EASTERN KS...AND PERHAPS FAR WESTERN MO/FAR SOUTHEAST NEB. A WATCH MAY BE NEEDED IN THE NEXT HOUR OR TWO. THUNDERSTORM COVERAGE IS EXPECTED TO INCREASE ACROSS MUCH OF NORTH CENTRAL INTO EASTERN KS...AND PERHAPS ADJACENT PORTIONS OF FAR SOUTHEAST NEB/WESTERN MO...THROUGH LATE AFTERNOON AND EARLY EVENING. THIS ACTIVITY IS LIKELY BOTH IN VICINITY OF THE SOUTHWEST-NORTHEAST ORIENTED FRONTAL ZONE FROM WEST CENTRAL KS INTO WEST CENTRAL IA...BUT ALSO WITH WARM ADVECTION ATOP THE RESIDUAL COLD POOL ACROSS EASTERN KS VIA EARLY DAY CONVECTION. WITHIN THIS CORRIDOR...POTENTIAL FOR SURFACE CONVECTION APPEARS LIMITED...ESPECIALLY WITH NORTHWARD EXTENT. ACCORDINGLY...ELEVATED CONVECTIVE MODE WILL LIKELY BE PREDOMINANT...WITH A PRIMARY HAZARD OF LARGE HAIL. RUC PROXIMITY SOUNDINGS PORTRAY ELEVATED MUCAPE OF 500-1000 J/KG IN PRESENCE OF STEEP MID LEVEL LAPSE RATE/STRONG CLOUD BEARING SHEAR ENVIRONMENT...FAVORABLE FOR AT LEAST ISOLATED LARGE HAIL. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EAX...OAX...TOP...ICT... 38989797 39429786 40229640 39479415 38339390 37949573 38399728 WWWW From Mcd at goshenarc.org Mon Apr 24 22:30:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 18:30:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242227 SWOMCD SPC MCD 242216 TXZ000-OKZ000-250015- MESOSCALE DISCUSSION 0642 NWS STORM PREDICTION CENTER NORMAN OK 0516 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242216Z - 250015Z MONITORING FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS NORTH CENTRAL INTO WEST CENTRAL TX...A CONDITIONAL POTENTIAL FOR VERY LARGE HAIL EXISTS. A SEVERE THUNDERSTORM WATCH COULD BE NEEDED IN THE NEXT HOUR OR TWO. ALTHOUGH REGION IS ON SOUTHERN FRINGE OF PRIMARY BACKGROUND FORCING FOR ASCENT/STRONGER MID LEVEL FLOW...AT LEAST ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP ACROSS NORTH CENTRAL INTO WEST CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. ALTHOUGH BOUNDARY LAYER CU HAS BEEN MODEST THUS FAR...VISIBLE TRENDS OVER THE PAST HALF HOUR FEATURES ISOLATED POCKETS OF MORE AGGRESSIVE CU...PERHAPS TIED TO A SUBTLE UPPER IMPULSE PER WATER VAPOR IMAGERY. ADJUSTED RUC SOUNDINGS/OBJECTIVE ANALYSIS SUGGESTS CONVECTIVE INHIBITION IS VIRTUALLY NIL IN VICINITY OF THE DRYLINE ACROSS NORTH CENTRAL/WEST CENTRAL TX...ROUGHLY LOCATED FROM NEAR ALTUS OK/WEST OF WICHITA FALLS TX...TO NEAR BROWNWOOD AND JUNCTION TX. WEST OF THE DRYLINE...DEEPLY MIXED PLUME WITH LOW TO MID 90S F TEMPERATURES IS IMPINGING UPON DEEPER MOISTURE EAST OF THE DRYLINE IN CENTRAL TX...CHARACTERIZED BY BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S/LOWER 70S. RUC PROXIMITY SOUNDINGS SUGGEST POTENTIAL FOR MLCAPE IN EXCESS OF 3000 J/KG. OBSERVED TRENDS IN THE JAYTON TX PROFILER CAPTURE MODEST INCREASE IN MID LEVEL WINDS OVER THE PAST FEW HOURS...WITH AROUND 40 KTS SOUTHWESTLY WINDS NOTED IN THE 4-6 KM LAYER AND ABOVE. GIVEN THE DEGREE OF INSTABILITY/ADEQUATE SHEAR...SUPERCELLS ARE LIKELY PROVIDED CONVECTIVE INITIATION...WITH POTENTIAL FOR VERY LARGE HAIL. A SEVERE WATCH MAY BE PRUDENT IN THE NEXT FEW HOURS...ESPECIALLY IF CONFIDENCE IN CONVECTIVE INITIATION/SCATTERED STORM COVERAGE INCREASES. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 30839846 30309926 30640019 31279972 32039927 32599920 34109902 33859780 33279748 32009760 31449794 WWWW From Mcd at goshenarc.org Mon Apr 24 22:32:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 18:32:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242229 SWOMCD SPC MCD 242229 TXZ000-OKZ000-250030- MESOSCALE DISCUSSION 0642 NWS STORM PREDICTION CENTER NORMAN OK 0529 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242229Z - 250030Z MONITORING FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS NORTH CENTRAL INTO WEST CENTRAL TX...A CONDITIONAL POTENTIAL FOR VERY LARGE HAIL EXISTS. A SEVERE THUNDERSTORM WATCH COULD BE NEEDED IN THE NEXT HOUR OR TWO. ALTHOUGH REGION IS ON SOUTHERN FRINGE OF PRIMARY BACKGROUND FORCING FOR ASCENT/STRONGER MID LEVEL FLOW...AT LEAST ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP ACROSS NORTH CENTRAL INTO WEST CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. ALTHOUGH BOUNDARY LAYER CU HAS BEEN MODEST THUS FAR...VISIBLE TRENDS OVER THE PAST HALF HOUR FEATURES ISOLATED POCKETS OF MORE AGGRESSIVE CU...PERHAPS TIED TO A SUBTLE UPPER IMPULSE PER WATER VAPOR IMAGERY. ADJUSTED RUC SOUNDINGS/OBJECTIVE ANALYSIS SUGGESTS CONVECTIVE INHIBITION IS VIRTUALLY NIL IN VICINITY OF THE DRYLINE ACROSS NORTH CENTRAL/WEST CENTRAL TX...ROUGHLY LOCATED FROM NEAR ALTUS OK/WEST OF WICHITA FALLS TX...TO NEAR BROWNWOOD AND JUNCTION TX. WEST OF THE DRYLINE...DEEPLY MIXED PLUME WITH LOW TO MID 90S F TEMPERATURES IS IMPINGING UPON DEEPER MOISTURE EAST OF THE DRYLINE IN CENTRAL TX...CHARACTERIZED BY BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S/LOWER 70S. RUC PROXIMITY SOUNDINGS SUGGEST POTENTIAL FOR MLCAPE IN EXCESS OF 3000 J/KG. OBSERVED TRENDS IN THE JAYTON TX PROFILER CAPTURE MODEST INCREASE IN MID LEVEL WINDS OVER THE PAST FEW HOURS...WITH AROUND 40 KTS SOUTHWESTLY WINDS NOTED IN THE 4-6 KM LAYER AND ABOVE. GIVEN THE DEGREE OF INSTABILITY/ADEQUATE SHEAR...SUPERCELLS ARE LIKELY PROVIDED CONVECTIVE INITIATION...WITH POTENTIAL FOR VERY LARGE HAIL. A SEVERE WATCH MAY BE PRUDENT IN THE NEXT FEW HOURS...ESPECIALLY IF CONFIDENCE IN CONVECTIVE INITIATION/SCATTERED STORM COVERAGE INCREASES. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 30839846 30309926 30640019 31279972 32039927 32599920 34109902 33859780 33279748 32009760 31449794 WWWW From Mcd at goshenarc.org Mon Apr 24 23:20:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 19:20:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242317 SWOMCD SPC MCD 242317 KSZ000-OKZ000-250045- MESOSCALE DISCUSSION 0644 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CDT MON APR 24 2006 AREAS AFFECTED...SOUTH CENTRAL KS AND WESTERN/CENTRAL OK CONCERNING...TORNADO WATCH 244... VALID 242317Z - 250045Z VALID PORTION OF TORNADO WATCH 244 CONTINUES UNTIL 02Z...WITH INCREASING POTENTIAL FOR VERY LARGE HAIL AND TORNADOES. SEVERE THUNDERSTORMS ARE ONGOING JUST EAST OF THE I-35 CORRIDOR IN SOUTH CENTRAL KS AND NORTH CENTRAL OK...FROM EAST OF WICHITA KS TO NEAR STILLWATER OK. MAIN HAZARD WITH THESE STORMS IN THE SHORT TERM WILL BE LARGE HAIL AS STORMS BEGIN TO OVERSPREAD RESIDUAL COLD POOL INTO SOUTHEAST KS/NORTHEAST OK. PRIMARY TORNADO POTENTIAL ACROSS TORNADO WATCH 244 SEEMINGLY REMAINS WITH STORMS THAT DEVELOP/MOVE EAST-NORTHEAST AND INTERACT WITH RESIDUAL OUTFLOW BOUNDARY ACROSS NORTH CENTRAL OK...ROUGHLY FROM NEAR ALVA/ENID OK TO JUST NORTH OF THE OKC METRO AREA. IN SOUTHWEST/WEST CENTRAL OK...RAPID THUNDERSTORM DEVELOPMENT IS OCCURRING ACROSS CADDO/COMANCHE/TILLMAN COUNTIES AS OF 2310Z. VERY MOIST/UNCAPPED AIRMASS IS IN PLACE AHEAD OF THESE STORMS INTO CENTRAL OK...THUS FURTHER DEVELOPMENT/SHORT TERM INTENSIFICATION APPEARS LIKELY AHEAD OF THE DRYLINE/COLD FRONT. AMBIENT WARM SECTOR AIRMASS IS CHARACTERIZED BY MLCAPE IN EXCESS OF 3000 J/KG. IN ADDITION...LOW LEVEL FLOW HAS BACKED TO SOUTH/SOUTHEAST OVER THE PAST FEW HOURS ACROSS CENTRAL/SOUTHWEST OK. ASIDE FROM VERY LARGE HAIL...MODESTLY ENLARGED LOW LEVEL HODOGRAPHS PER ADJUSTED TLX WSR-88D VAD IS SUFFICIENT FOR LOW LEVEL STORM ROTATION/POTENTIAL TORNADOES AS STORMS INTENSIFY/MOVE EAST-NORTHEAST INTO CENTRAL OK. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN...DDC... 37629849 37919818 38159753 37789660 36619637 35639671 34429702 34159790 34359880 35509895 36759870 37269863 WWWW From Mcd at goshenarc.org Tue Apr 25 01:30:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 21:30:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250127 SWOMCD SPC MCD 250127 OKZ000-KSZ000-TXZ000-250200- MESOSCALE DISCUSSION 0645 NWS STORM PREDICTION CENTER NORMAN OK 0827 PM CDT MON APR 24 2006 AREAS AFFECTED...KS...OK CONCERNING...TORNADO WATCH 244...246... VALID 250127Z - 250200Z INTENSE SUPERCELLS MOVING ACROSS CNTRL/NERN OK EXPECTED TO CONTINUE TO POSE A THREAT OF VERY LARGE HAIL...DAMAGING WINDS...AND PERHAPS A TORNADO OR TWO. A NEW TORNADO WATCH REPLACING PORTIONS OF WW 244 AND WW 246 ACROSS CNTRL AND NERN OK WILL BE ISSUED SHORTLY. ENVIRONMENT AHEAD OF ONGOING LONG-TRACK SUPERCELLS...FROM OSAGE COUNTY AND TULSA AREA SWWD ACROSS OKLAHOMA CITY METRO AND POINTS SOUTH...WILL CONTINUE TO SUPPORT STRONG STORM ROTATION GIVEN ABUNDANT INSTABILITY AND STRONG SHEAR. ACTIVITY CROSSING THE RESIDUAL OUTFLOW BOUNDARY ACROSS NERN OK APPEARS TO BE DEVELOPING UPSCALE AND INTO A LARGER MCS WITH POTENTIAL FOR WIND DAMAGE DEVELOPING INTO THE TULSA AREA INCREASING. OTHER STORMS...AHEAD OF THE DRYLINE...REMAIN DISCRETE AND LONG-LIVED WITH OCCASIONAL MESOCYCLONES CONTINUING TO APPEAR IN SRM LOOPS FROM AREA RADAR. A CONTINUING THREAT FOR VERY LARGE HAIL AND ISOLATED BRIEF TORNADOES WILL PERSIST WITH THIS ACTIVITY AS IT DEVELOPS EWD AT 15-20KT. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN... 34109696 34159908 35099927 35019840 36189865 37109819 38349798 38319722 37269672 36639653 35209664 WWWW From Mcd at goshenarc.org Tue Apr 25 03:33:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 23:33:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250331 SWOMCD SPC MCD 250330 ARZ000-MOZ000-OKZ000-KSZ000-TXZ000-250500- MESOSCALE DISCUSSION 0646 NWS STORM PREDICTION CENTER NORMAN OK 1030 PM CDT MON APR 24 2006 AREAS AFFECTED...SRN TO NERN OK CONCERNING...TORNADO WATCH 247... VALID 250330Z - 250500Z EXPECT PRE-FRONTAL LINEAR MCS OVER NERN OK TO CONTINUE TO WEAKEN AS ACTIVITY INGESTS GREATER STABILITY ON THE COOL SIDE OF RESIDUAL OUTFLOW BOUNDARY. THIS LINE WAS MOVING EAST AT UP TO 35KT IN SOME AREAS SO A MARGINAL SEVERE WIND AND HAIL THREAT MAY STILL EXIST ACROSS VALID PORTIONS OF THE WATCH FOR ANOTHER HOUR OR SO. A FEW INTENSE STORMS WITH LARGE HAIL AND WEAK/BRIEF TORNADO THREAT REMAIN POSSIBLE IN THE WARM SECTOR SOUTH OF OKC AREA. IN ADDITION TO LONG-LIVED SUPERCELL OVER GARVIN AND PONTOTOC COUNTIES...ADDITIONAL STORMS APPEAR TO BE FORMING ALONG THE COLD FRONT NOW MOVING EAST TOWARD I35/I44. AIR MASS AHEAD OF THIS CONVECTION REMAINS VERY UNSTABLE AND SHEAR WILL CONTINUE TO SUPPORT UPDRAFT INTENSIFICATION. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...ICT...FWD...OUN... 34009797 34129837 35779684 36469661 37029640 36669588 36589532 36659463 35429439 35059490 34989554 34659550 34189576 33889659 33819713 33879798 WWWW From Mcd at goshenarc.org Tue Apr 25 06:06:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 02:06:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250604 SWOMCD SPC MCD 250603 ARZ000-250800- MESOSCALE DISCUSSION 0647 NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS WRN...CENTRAL AND NRN AR. CONCERNING...CONVECTIVE TRENDS VALID 250603Z - 250800Z SEVERE POTENTIAL SHOULD DIMINISH WITH NWRN AR COMPLEX...THEREFORE ADDITIONAL WW NOT ANTICIPATED ATTM IN ITS PROJECTED PATH. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY -- LEFT BEHIND BY AFTERNOON MCS -- FROM NEAR PBF WNWWD ACROSS LATIMER/PUSHMATAHA COUNTY LINE. LINE OF TSTMS -- NOW MOVING ESEWD 40-45 KT ACROSS NERN AR -- IS EXPECTED TO MOVE INTO MORE STABLE AIR MASS ALOFT ACROSS CENTRAL/N-CENTRAL AR AND WEAKEN. ITS OWN OUTFLOW ALREADY HAS SURGED 10-20 NM AHEAD OF LEADING EDGE OF STRONGEST REFLECTIVITIES...AS EVIDENT IN ANIMATED REFLECTIVITY IMAGERY FROM FSM. THERE MAY STILL BE OCCASIONAL GUSTS BELOW 50 KT SEVERE CRITERIA -- BUT CAPABLE OF DAMAGE TO TREES AND WEAK STRUCTURES -- ALONG WITH INTERMITTENT/MRGLLY SEVERE HAIL. ACTIVITY IS ROOTED IN LAYER OF ELEVATED BUOYANCY ATOP OLDER OUTFLOW BOUNDARY...ELEVATED MUCAPES DIMINISHING FROM AROUND 1500 J/KG ALONG OK/AR BORDER...TO LESS THAN 500 J/KG FROM LIT EWD. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...TSA... 35119441 35509353 35989313 36389287 36179142 35779098 34799158 34559302 34909414 WWWW From Mcd at goshenarc.org Tue Apr 25 06:14:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 02:14:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250612 SWOMCD SPC MCD 250611 ARZ000-TXZ000-OKZ000-250715- MESOSCALE DISCUSSION 0648 NWS STORM PREDICTION CENTER NORMAN OK 0111 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS SERN OK...NE TX...SWRN AR. CONCERNING...TORNADO WATCH 247... VALID 250611Z - 250715Z ORGANIZED SEVERE POTENTIAL MAY LINGER WITH TSTM CLUSTER EVIDENT AT 545Z OVER PORTIONS COAL/SRN PITTSBURG/NWRN ATOKA COUNTIES. THIS ACTIVITY SHOULD MOVE EWD/ESEWD ACROSS SERN OK WITH SOME POTENTIAL TO BACKBUILD TOWARD RED RIVER VALLEY BEFORE ENTERING AR. REPLACEMENT WW MAY BE NEEDED SOON. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY -- LEFT BEHIND BY AFTERNOON MCS -- FROM NEAR PBF WNWWD ACROSS LATIMER/PUSHMATAHA COUNTY LINE. SFC COLD FRONT IS ANALYZED FROM TUL AREA SWWD ACROSS GARVIN COUNTY...THEN NEAR SPS. FRONT SHOULD CONTINUE MOVING SEWD 10-20 KT. AXIS OF MAX 850 MB MOISTURE TRANSPORT IS PROGGED TO SHIFT EWD WITH VEERING LLJ TOWARD CHOCTAW/MCCURTAIN COUNTIES...IN AGREEMENT WITH CORFIDI-MCS MOTION VECTORS INDICATING SLOW TRACK THAT WAY. EXPECT INFLOW LAYER FOR SERN OK COMPLEX TO BECOME PROGRESSIVELY MORE ELEVATED AGL THROUGH REMAINDER TONIGHT. HOWEVER...MODIFIED RAOBS AND RUC SOUNDING DATA INDICATES SOME PARCELS ACROSS S-CENTRAL/SERN OK -- AHEAD OF COLD FRONT AND GENERALLY S-SW OF ONGOING ACTIVITY -- REMAIN NEARLY SFC-BASED. ANY ACTIVITY DEVELOPING FARTHER NW AND N IN WW 247 MAY PRODUCE OCNL HAIL NEAR SEVERE LEVELS...BUT NOT TORNADOES BECAUSE OF ITS MORE ELEVATED/DISORGANIZED CHARACTER. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 34409695 35529627 35689554 35399462 35239419 34979404 34599396 34449393 34229406 33849424 33539468 33489512 33469583 33609655 WWWW From Mcd at goshenarc.org Tue Apr 25 10:01:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 06:01:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250958 SWOMCD SPC MCD 250957 ARZ000-TXZ000-OKZ000-251200- MESOSCALE DISCUSSION 0649 NWS STORM PREDICTION CENTER NORMAN OK 0457 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS N-CENTRAL/NE TX...S-CENTRAL/SERN OK...SWRN-CENTRAL AR. CONCERNING...SEVERE THUNDERSTORM WATCH 248... VALID 250957Z - 251200Z CURRENT CONVECTIVE TRENDS AND MODIFIED SOUNDINGS INDICATE DIMINISHING SEVERE POTENTIAL OVER WW AREA...AND ALSO...WITH EWD EXTENT ACROSS AR AHEAD OF ONGOING MCS. ACCORDINGLY...PORTIONS WW MAY BE CANCELED BEFORE SCHEDULED 12Z EXPIRATION. MEANWHILE...WW SHOULD BE CLEARED BEHIND FROPA. SFC ANALYSIS INDICATES COLD FRONT AT 930Z FROM JACK/COOKE COUNTIES TX NEWD THROUGH HUGHES COUNTY OK...BECOMING DIFFUSE FARTHER N AMIDST BLEND OF CONVECTIVE OUTFLOWS. EXPECT LOW LEVEL AIR MASS TO STABILIZE BEHIND THIS FRONT FROM W-E AND TO BECOME PROGRESSIVELY LESS CONDUCIVE FOR SVR TSTM DEVELOPMENT. MEANWHILE...MCS HAS EXITED ERN PORTIONS WW...AND REMAINS LARGELY BELOW SEVERE LEVELS AS IT MOVES EWD ACROSS WRN/CENTRAL AR ATTM. MODIFIED RAOBS AND RUC SOUNDINGS INDICATE STRONG MERIDIONAL GRADIENT IN ELEVATED BUOYANCY REMAINS ACROSS CENTRAL AR. COMPLEX SOON WILL MOVE INTO ENVIRONMENT MUCH MORE HOSTILE FOR SUSTAINING DEEP CONVECTION WITH MUCAPES DROPPING BELOW 500 J/KG. WIDELY SCATTERED CONVECTION MAY CONTINUE TO DEVELOP OVER ITS OWN OUTFLOW POOL OVER SERN OK...HOWEVER THIS AIR MASS WILL CONTAIN MORE ELEVATED BUOYANT LAYER WITH WEAKER CAPE THAN WAS AVAILABLE TO INITIAL ACTIVITY. STRONGER MUCAPE -- UP TO 2500 J/KG -- REMAINS E OF COLD FRONT AND S OF COLLECTIVE OUTFLOW BOUNDARY...OVER RED RIVER REGION OF SERN OK/NERN TX. STRENGTHENING CAPPING WITH SWD EXTENT...AND WEAK EFFECTIVE SHEARS OF 25 KT OR LESS OVER MUCH OF THIS REGION...LEND CONSIDERABLE DOUBT ABOUT FURTHER POTENTIAL FOR ORGANIZED SEVERE. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 34699535 34459378 34769305 35129294 35089187 34429168 33679222 33359530 33689719 WWWW From mcd at goshenarc.org Tue Apr 25 15:45:38 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 11:45:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251542 SWOMCD SPC MCD 251542 WVZ000-VAZ000-KYZ000-TNZ000-251745- MESOSCALE DISCUSSION 0650 NWS STORM PREDICTION CENTER NORMAN OK 1042 AM CDT TUE APR 25 2006 AREAS AFFECTED...ERN KY/ERN TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251542Z - 251745Z CONVECTIVE TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE THREAT. A WW COULD BECOME NECESSARY...PERHAPS BY EARLY AFTERNOON. MID-LEVEL CYCLONIC VORTICITY CENTER....ASSOCIATED WITH REMNANTS OF OVERNIGHT CONVECTIVE CLUSTER...IS EVIDENT IN OBSERVATIONAL DATA... MIGRATING ACROSS WESTERN KENTUCKY AT THE MOMENT. THIS FEATURE IS ON SOUTHERN PERIPHERY OF MODERATELY STRONG CONFLUENT MID-LEVEL FLOW REGIME...AND IS EXPECTED TO BECOME INCREASINGLY SHEARED AS IT ACCELERATES TOWARD THE CENTRAL APPALACHIANS. HOWEVER...FORCING IS EXPECTED TO REMAIN SUFFICIENT TO SUPPORT INCREASING CONVECTIVE DEVELOPMENT INTO THE AFTERNOON HOURS ACROSS CENTRAL/EASTERN KENTUCKY AND PARTS OF NORTHEASTERN TENNESSEE. ONGOING ACTIVITY SEEMS LIKELY TO BECOME INCREASINGLY BASED IN MOIST BOUNDARY LAYER EAST OF BOWLING GREEN SHORTLY. AND...A GRADUAL INTENSIFICATION IS EXPECTED AS INFLOW FROM A DESTABILIZING BOUNDARY LAYER ACROSS THE LEXINGTON/LONDON/SOMERSET AREAS STRENGTHENS BY 18-19Z. THIS SEEMS LIKELY TO BE ACCOMPANIED BY INCREASING POTENTIAL FOR DAMAGING SURFACE GUSTS...AIDED BY BELT OF 30 TO 40 KT WESTERLY LOWER/MID TROPOSPHERIC FLOW. STRONGER STORMS MAY ALSO PRODUCE SOME HAIL...BUT WITH CAPE GENERALLY AROUND 1000 J/KG...PEAK HAIL SIZES MAY REMAIN MARGINALLY SEVERE. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...MRX...JKL...ILN...LMK...OHX... 37718582 38328513 38538426 38528328 38328240 37728197 36908231 36018339 35948465 35918570 36488624 37028604 37348591 WWWW From mcd at goshenarc.org Tue Apr 25 16:10:25 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 12:10:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251607 SWOMCD SPC MCD 251607 MSZ000-LAZ000-TXZ000-251730- MESOSCALE DISCUSSION 0651 NWS STORM PREDICTION CENTER NORMAN OK 1107 AM CDT TUE APR 25 2006 AREAS AFFECTED...SE TX...SRN LA...SRN MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251607Z - 251730Z A WW IS NOT ANTICIPATED IN THE NEAR TERM...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE POTENTIAL. OUTFLOW BOUNDARY GENERATED BY OVERNIGHT CONVECTION IS ADVANCING SLOWLY SOUTHWARD THROUGH THE LOWER MISSISSIPPI VALLEY. THIS FEATURE HAS YET TO BECOME FOCUS FOR VIGOROUS NEW CONVECTIVE DEVELOPMENT...BUT BROAD LOW-LEVEL WARM ADVECTION REGIME NORTH AND SOUTH OF THE BOUNDARY IS PROVIDING SUPPORT FOR INCREASING CONVECTIVE DEVELOPMENT. MOST VIGOROUS STORMS THROUGH 17-18Z SEEM LIKELY TO EVOLVE TO THE SOUTH OF THE OUTFLOW...WITH ADDITIONAL ACTIVITY EVENTUALLY DEVELOPING ALONG THE BOUNDARY ITSELF. AS CONVECTIVE TEMPERATURES ARE APPROACHED...CONVECTION WILL BECOME ROOTED IN MIXED BOUNDARY LAYER WITH CAPE IN EXCESS OF 2000 J/KG. LOW-LEVEL WIND FIELDS ARE RATHER WEAK...BUT MID/UPPER FLOW APPEARS STRONG ENOUGH FOR DEEP LAYER SHEAR FAVORABLE FOR AT LEAST BRIEF MID-LEVEL UPDRAFT ROTATION...WHICH WILL ENHANCE POTENTIAL FOR HAIL IN STRONGER CELLS. LOCALIZED DOWNBURSTS ARE ALSO POSSIBLE. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LCH...SHV...HGX...FWD... 31049638 31759549 32359444 31919290 31979098 31939035 30818971 30118995 29889167 30029335 29899501 30159642 WWWW From mcd at goshenarc.org Tue Apr 25 18:38:23 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 14:38:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251835 SWOMCD SPC MCD 251835 TXZ000-252030- MESOSCALE DISCUSSION 0652 NWS STORM PREDICTION CENTER NORMAN OK 0135 PM CDT TUE APR 25 2006 AREAS AFFECTED...S-CNTRL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251835Z - 252030Z THUNDERSTORM INITIATION APPEARS MOST PROBABLE BETWEEN 21-23Z. A WW WILL LIKELY BE NEEDED LATER THIS AFTERNOON. 18Z SURFACE ANALYSIS AND MODIFIED RUC SOUNDINGS SHOW A WEAKENING CAP ACROSS S-CNTRL TX ALONG A SYNOPTIC COLD FRONT FROM NEAR DRT NEWD TO SAT AND CLL. VISIBLE SATELLITE HAS SHOWN AGITATED CUMULUS ALONG THE FRONT OVER THE PAST FEW HOURS. LOW-LEVEL CONVERGENCE ALONG THE FRONT IS WEAK AND IS EXPECTED TO REMAIN SO...WITH A WEAK MESO HIGH JUST N OF IAH. HOWEVER...AS TEMPERATURES CONTINUE TO WARM...THE FRONT SHOULD PROVIDE ENOUGH LIFT TO INITIATE THUNDERSTORMS IN THE LATE AFTERNOON NEAR THE MEXICO BORDER REGION AND THEN NEWD WITH TIME. STRONG INSTABILITY WILL EXIST WITH MLCAPES OF 3000 TO 4000 J/KG...ALTHOUGH SHEAR THROUGHOUT THE LOW AND MOST OF THE MID-LEVELS IS FAIRLY WEAK. MODEST WLY FLOW FROM 500 MB AND ABOVE WILL SUPPORT STORM ORGANIZATION GIVEN THE HIGH CAPE VALUES. ISOLATED SUPERCELLS PRODUCING LARGE HAIL APPEARS TO BE THE MAIN SEVERE THREAT. ..GRAMS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...CRP...EWX... 29310086 29530088 29799967 30049797 30599653 30509541 29409480 28729560 27669772 27569961 WWWW From mcd at goshenarc.org Tue Apr 25 19:28:18 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 15:28:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251925 SWOMCD SPC MCD 251925 VAZ000-WVZ000-TNZ000-KYZ000-OHZ000-252130- MESOSCALE DISCUSSION 0653 NWS STORM PREDICTION CENTER NORMAN OK 0225 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN KY...CNTRL/SRN WV...WRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251925Z - 252130Z TRENDS ARE BEING MONITORED. IT REMAINS UNCERTAIN WHETHER INTENSIFICATION OF CONVECTIVE DEVELOPMENT...WHICH IS STILL EXPECTED...WILL BECOME SUFFICIENT TO WARRANT A WW. AREA OF STRONGER FORCING ASSOCIATED WITH MID-LEVEL IMPULSE CONTINUES TO SHIFT TOWARD THE CENTRAL APPALACHIANS. LATEST RUC MODEL SUGGESTS THIS FEATURE MAY BE CONTRIBUTING TO STRENGTHENING WESTERLY LOWER/MID TROPOSPHERIC FLOW ACROSS KENTUCKY/TENNESSEE...JUST SOUTH OF STRONGER CONFLUENT MID-LEVEL REGIME ACROSS THE UPPER OHIO VALLEY. LACK OF MORE SUBSTANTIAL DESTABILIZATION DUE TO RATHER WEAK MID-LEVEL LAPSE RATES APPEARS TO BE PRIMARY LIMITING FACTOR TO MORE VIGOROUS CONVECTIVE DEVELOPMENT...AND THIS MAY REMAIN THE CASE. HOWEVER...CAPE OF 500 TO 1000 J/KG IN MOIST MIXED BOUNDARY LAYER ACROSS CENTRAL/EASTERN KENTUCKY PROBABLY WILL STILL BE SUPPORTIVE OF AT LEAST SOME INTENSIFICATION TO ONGOING ACTIVITY. AND...A MORE ORGANIZED CLUSTER COULD SLOWLY EVOLVE IN 40+ KT MEAN FLOW LATE THIS AFTERNOON. IF THIS OCCURS...AT LEAST A RISK FOR SPORADIC DAMAGING WIND GUSTS SHOULD INCREASE BY THE 21-23Z TIME FRAME ACROSS WEST VIRGINIA...WHERE DRIER BUT DEEPLY MIXED BOUNDARY LAYER MAY ENHANCE EVAPORATIVE COOLING IN DOWNDRAFTS. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX...MRX...JKL...OHX... 38498313 38548273 38728188 39128048 38487975 38017971 37108027 36528188 36288303 36158406 36528482 37408384 37948348 WWWW From mcd at goshenarc.org Tue Apr 25 20:14:20 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 16:14:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252011 SWOMCD SPC MCD 252011 TNZ000-KYZ000-ILZ000-MOZ000-ARZ000-252115- MESOSCALE DISCUSSION 0654 NWS STORM PREDICTION CENTER NORMAN OK 0311 PM CDT TUE APR 25 2006 AREAS AFFECTED...SRN MO...NRN AR..PARTS OF WRN KY/TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252011Z - 252115Z A WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE THREAT. MID-LEVEL COOLING/FORCING FOR UPWARD VERTICAL MOTION...ASSOCIATED WITH UPPER TROUGH SHIFTING EAST OF THE CENTRAL PLAINS...APPEARS TO BE PRIMARY CONTRIBUTOR TO RECENT CONVECTIVE DEVELOPMENT ACROSS SOUTHWEST MISSOURI. THIS ACTIVITY APPEARS ROOTED IN LINGERING MOIST LAYER ABOVE FRONTAL INVERSION...BUT EASTWARD DEVELOPMENT IN CLOSER PROXIMITY TO SURFACE FRONT ALONG THE EASTERN ARKANSAS/MISSOURI BORDER AREA SEEMS POSSIBLE BY 21-22Z. LOW-LEVEL FLOW ACROSS THIS AREA IS GENERALLY WEAKENING...BUT 50+ KT 500 MB JET STREAK IS CONTRIBUTING TO FAVORABLE DEEP LAYER SHEAR FOR UPDRAFT ROTATION. ISOLATED CONVECTIVE DEVELOPMENT COULD EVOLVE INTO A CONVECTIVE CLUSTER...BUT BOUNDARY LAYER DESTABILIZATION OF ANY SIGNIFICANCE IN WAKE OF OVERNIGHT MESOSCALE CONVECTIVE SYSTEM MAY BE CONFINED TO A RELATIVELY NARROW PRE-FRONTAL CORRIDOR. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...MEG...LZK...SGF... 36809202 36849127 36989060 37239021 37268948 37008893 36388906 36028950 35859012 35819083 35969192 36179217 WWWW From mcd at goshenarc.org Tue Apr 25 20:56:22 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 16:56:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252052 SWOMCD SPC MCD 252052 TXZ000-252245- MESOSCALE DISCUSSION 0655 NWS STORM PREDICTION CENTER NORMAN OK 0352 PM CDT TUE APR 25 2006 AREAS AFFECTED...N-CNTRL/NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252052Z - 252245Z SCATTERED ELEVATED THUNDERSTORMS ARE EXPECTED TO CONTINUE ALONG MID-LEVEL COLD FRONT...WITH MARGINALLY SEVERE HAIL THE MAIN THREAT. A WW IS NOT ANTICIPATED GIVEN MARGINAL AND FAIRLY ISOLATED NATURE OF THREAT. ELEVATED THUNDERSTORMS HAVE DEVELOPED ACROSS PORTIONS OF N-CNTRL TX AHEAD OF A 700 MB COLD FRONT. RUC SOUNDINGS INDICATE MOST UNSTABLE PARCELS NEAR THIS LEVEL POSSESSING CAPES OF AROUND 500 TO 750 J/KG. EFFECTIVE SHEAR IS MODEST /AROUND 30 TO 40 KTS/. THIS WILL SUPPORT ORGANIZED UPDRAFTS WHICH WILL PRODUCE HAIL...SOME OF WHICH COULD BE MARGINALLY SEVERE. QPF SIGNAL FROM 09Z SREF INDICATES ACTIVITY SHOULD PERSIST AND SPREAD EWD INTO PORTIONS OF NERN TX INTO THE EVENING. ..GRAMS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...FWD...SJT... 31200114 31650059 32369939 32759848 33259733 33589602 33319552 32829538 32169547 31679618 31339730 31049876 30859989 30930063 WWWW From mcd at goshenarc.org Tue Apr 25 22:19:12 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 18:19:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252216 SWOMCD SPC MCD 252216 VAZ000-NCZ000-TNZ000-252345- MESOSCALE DISCUSSION 0656 NWS STORM PREDICTION CENTER NORMAN OK 0516 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TN...SWRN VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252216Z - 252345Z THE CHANCE FOR ORGANIZED TSTMS APPEARS TO BE INCREASING ACROSS THE CNTRL APPALACHIANS AND INTO PORTIONS OF SWRN VA AND WRN NC THIS EVENING. A WATCH MAY BE NEEDED OVER PARTS OF THE REGION SHORTLY. SURFACE COLD FRONT WAS SAGGING SWD/SEWD TOWARD SWRN VA AND NERN TN WITH STORMS AHEAD OF THIS BOUNDARY INCREASING. LIFT ACROSS THE REGION WAS BEING FURTHER ENHANCED BY DIFFLUENT MID LEVEL FLOW AHEAD OF PROGRESSIVE AND LOW-AMPLITUDE SHORT WAVE TROUGH APPROACHING FROM KY/TN. THIS IMPULSE IS FORECAST TO INDUCE SURFACE WAVE DEVELOPMENT NEAR THE FRONT AS IT MOVES INTO VA LATER TONIGHT. DIURNAL HEATING HAS CONTRIBUTED TO LARGE TEMPERATURE-DEWPOINT SPREADS...AND THE DEVELOPMENT OF STEEP LOW TO MID LEVEL LAPSE RATES. AS CONVECTION INCREASES AHEAD OF THE FRONT AND NEAR THE DEVELOPING WAVE MOVING ACROSS THE REGION TONIGHT... PRIMARY THREAT APPEARS TO BE FROM A FEW STRONG TO DAMAGING WIND GUSTS WITH STORMS ORGANIZED INTO LINES OR CLUSTERS. AREAL COVERAGE MAY REMAIN LIMITED GIVEN TIME OF DAY...BUT FAVORABLE LARGE SCALE FORCING MAY SUSTAIN THE SEVERE THREAT INTO THE NIGHT. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...RNK...GSP...MRX... 36517883 35588023 35308204 35328309 35408372 35658392 36368299 36828185 37298043 37447995 37497933 37397896 36867861 WWWW From mcd at goshenarc.org Wed Apr 26 00:23:37 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 20:23:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260020 SWOMCD SPC MCD 260020 ALZ000-KYZ000-TNZ000-ILZ000-MOZ000-ARZ000-MSZ000-260115- MESOSCALE DISCUSSION 0657 NWS STORM PREDICTION CENTER NORMAN OK 0720 PM CDT TUE APR 25 2006 AREAS AFFECTED...SERN MO...SRN IL...WRN KY/TN...NERN AR CONCERNING...SEVERE THUNDERSTORM WATCH 250... VALID 260020Z - 260115Z A FEW SEVERE STORMS WITH LARGE HAIL AND POTENTIALLY DAMAGING WINDS WILL SPREAD EAST ACROSS EXTREME NERN AR AND PARTS OF WRN TN OVER THE NEXT HOUR. MOST INTENSE LONG-LIVED SUPERCELL HAS MOVED ACROSS THE MO BOOTHEEL LAST HOUR WITH A REPORT OF SIGNIFICANT HAIL TO 4 INCHES IN DIAMETER. THIS CELL...WHICH WAS NEAR DEVELOPING FRONTAL WAVE/LOW WILL CONTINUE MOVING ACROSS DYER COUNTY TN OVER THE NEXT 45 MINUTES BEFORE MOVING INTO GIBSON AND NRN CROCKETT COUNTIES THEREAFTER. ADDITIONAL CELLS WERE INCREASING AHEAD OF THE COLD FRONT IN NERN AR. STRONG LARGE SCALE FORCING ACROSS THE WARM SECTOR FROM DIFFLUENT MID LEVEL JET STREAK...AND VERY STEEP RATES EVIDENT IN LATEST LITTLE ROCK RAOB...WERE LIKELY CONTRIBUTING TO THE INCREASE IN THIS ACTIVITY. POTENTIAL FOR LARGE HAIL...AND POSSIBLY WINDS TO AROUND 50KT...COULD INCREASE ACROSS MISSISSIPPI COUNTY AR IN ABOUT AN HOUR. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...HUN...PAH...MEG...LSX...LZK...SGF... 37069121 36499122 36509252 35719239 35679290 35479288 35339199 35039204 34919058 35019013 35008793 35848798 35938811 36628802 36638768 36968764 37068797 37268817 37448788 37548796 37388877 37218864 37378953 37068998 37329007 37279063 WWWW From mcd at goshenarc.org Wed Apr 26 00:34:58 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 20:34:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260032 SWOMCD SPC MCD 260031 TXZ000-260200- MESOSCALE DISCUSSION 0658 NWS STORM PREDICTION CENTER NORMAN OK 0731 PM CDT TUE APR 25 2006 AREAS AFFECTED...S-CNTRL/SERN TX CONCERNING...SEVERE THUNDERSTORM WATCH 249... VALID 260031Z - 260200Z SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL WILL CONTINUE ACROSS SWRN PORTION OF WATCH. ADDITIONAL DEVELOPMENT IS LIKELY FURTHER NEWD IN THE NEXT FEW HOURS. CONTINUE WW. AN UNSTABLE ENVIRONMENT EXISTS ACROSS PORTIONS OF S-CNTRL TX WITH MLCAPES OF 2500 TO 3500 J/KG /PER 00Z CRP SOUNDING/. SUPERCELLS WILL CONTINUE TO THRIVE FOR THE NEXT FEW HOURS FROM AROUND KARNES TO JIM WELLS COUNTIES. ADDITIONAL DEVELOPMENT TO THE W OF THESE AREAS SUGGESTS A TRANSITION TO A MORE MULTICELLULAR MODE MAY OCCUR AFTER DARK. IMPRESSIVE SWD MOVING SUPERCELL ACROSS SRN DUVAL COUNTY WOULD APPEAR TO HAVE SOME TORNADIC POTENTIAL GIVEN MOVEMENT. HOWEVER...A VERY WEAK LOW-LEVEL WIND FIELD PER 00Z CRP SOUNDING AND INCREASING BOUNDARY LAYER STABILIZATION WILL TEND TO MITIGATE THIS THREAT. FURTHER NE...TIMING OF CONVECTIVE DEVELOPMENT IS STILL UNCERTAIN. 00Z LCH SOUNDING AND MODIFIED RUC SOUNDINGS SUGGEST THE AREA IS UNCAPPED. CELLS ARE BEGINNING TO INITIATE IN LAVACA COUNTY AND ADDITIONAL DOWNSTREAM DEVELOPMENT APPEARS LIKELY WITHIN THE NEXT FEW HOURS. 18Z NAM-WRF GUIDANCE INDICATED THE LOW-LEVEL MOISTURE CONVERGENCE ALONG THE COLD FRONT WILL STRENGTHEN BETWEEN 00 AND 03Z. THE ENVIRONMENT IS UNSTABLE WITH AROUND 2500 J/KG MLCAPE PER 00Z LCH SOUNDING. ALTHOUGH SHEAR IS RATHER WEAK...THE DEGREE OF INSTABILITY WILL SUPPORT A LARGE HAIL THREAT. ..GRAMS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...HGX...CRP...EWX...BRO... 28290026 28990041 29069958 29029872 29359756 30219652 31139492 30349466 29699439 29339433 28669530 27639721 27309783 27289887 27289932 WWWW From mcd at goshenarc.org Wed Apr 26 01:48:32 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 21:48:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260145 SWOMCD SPC MCD 260145 ARZ000-LAZ000-TXZ000-260315- MESOSCALE DISCUSSION 0659 NWS STORM PREDICTION CENTER NORMAN OK 0845 PM CDT TUE APR 25 2006 AREAS AFFECTED...EXTREME SRN AR...WRN LA...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 260145Z - 260315Z CHANCES FOR STRONG TO SEVERE TSTM DEVELOPMENT MAY BE INCREASING ACROSS PORTIONS OF NERN TX...WRN LA...AND POSSIBLY EXTREME SRN AR...LATE THIS EVENING. THESE AREAS ARE BEING MONITORED FOR A POSSIBLE SEVERE TSTM WATCH. PERSISTENT CLUSTER OF ELEVATED...BUT INTENSE...CONVECTION MOVING EAST ACROSS PARTS OF EAST TX APPEARS TO BE IN RESPONSE TO WEAK MID LEVEL IMPULSE ACTING ON VERY UNSTABLE CONDITIONS ABOVE SURFACE-BASED FRONTAL INVERSION. FARTHER EAST...FROM TX/LA BORDER NWD/EWD ACROSS THE MS VALLEY...WARM SECTOR AIR MASS AHEAD OF THE COLD FRONT HAS BEEN GRADUALLY RECOVERING IN THE WAKE OF EARLIER MCS. LATEST RUC...GFS...AND ETAKF GUIDANCE ALL SUGGEST RENEWED DEEP CONVECTION SHOULD OCCUR ALONG THE FRONT THROUGH LATE TONIGHT...POSSIBLY EVOLVING INTO ANOTHER MCS THAT WOULD THEN DEVELOP EAST ACROSS THE LOWER MS VALLEY. THIS SCENARIO APPEARS PROBABLE BASED ON EVENING RAOB DATA FROM SHV AND LCH INDICATING LITTLE INHIBITION EXISTS WITHIN A VERY MOIST AND UNSTABLE ENVIRONMENT. DEEP LAYER WLY FLOW AND ADEQUATE SHEAR IS EXPECTED TO REMAIN SUPPORTIVE OF BOTH INITIAL CELL ROTATION...AND EVENTUALLY ACCELERATING COLD POOLS. THUS... INCREASINGLY POTENTIAL FOR BOTH LARGE HAIL AND DAMAGING WINDS SUGGESTS A WATCH MAY BE NEEDED OVER THE AREA IN ABOUT AN HOUR. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...LCH...SHV... 30209348 30489444 31099454 32939370 33289327 33249212 31629214 WWWW From mcd at goshenarc.org Wed Apr 26 02:16:03 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 22:16:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260213 SWOMCD SPC MCD 260213 NCZ000-VAZ000-TNZ000-260415- MESOSCALE DISCUSSION 0660 NWS STORM PREDICTION CENTER NORMAN OK 0913 PM CDT TUE APR 25 2006 AREAS AFFECTED...NRN NC...SWRN/SRN VA CONCERNING...SEVERE THUNDERSTORM WATCH 251... VALID 260213Z - 260415Z STRONG AND ISOLATED SEVERE STORMS WILL CONTINUE TO MOVE ACROSS SRN VA THE NC PIEDMONT THROUGH MIDNIGHT. AS COLD FRONT REDEVELOPS EAST OF THE APPALACHIANS...STRONG LARGE SCALE ASCENT ASSOCIATED WITH AN APPROACHING MID/UPPER LEVEL IMPULSE WILL MAINTAIN TSTMS AHEAD OF THE FRONT. WARM AND RELATIVELY DRY BOUNDARY LAYER MAY RESULT IN A BRIEF DAMAGING WIND THREAT FROM LINES AND CLUSTERS OF TSTMS MOVING EAST LATE THIS EVENING. EARLIER GSO RAOB INDICATED STEEP BOUNDARY LAYER LAPSE RATES AND SUFFICIENT UNIDIRECTIONAL SHEAR TO MAINTAIN A SEVERE WIND AND MARGINAL HAIL THREAT FROM A FEW OF THE MORE ROBUST UPDRAFTS. HOWEVER...OVERALL SEVERE POTENTIAL SHOULD GRADUALLY DECREASE AS BOUNDARY LAYER COOLING INHIBITS STRONGER DOWNDRAFTS. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...GSP...MRX... 35168283 35688304 36478201 36748133 37008131 37637998 37587963 37737923 37607893 37737853 37557771 37327726 37027740 36897754 36697752 36517711 36117724 35847737 35677764 35837775 35747825 35547884 35428027 WWWW From mcd at goshenarc.org Wed Apr 26 02:41:03 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 22:41:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260238 SWOMCD SPC MCD 260238 TXZ000-260415- MESOSCALE DISCUSSION 0661 NWS STORM PREDICTION CENTER NORMAN OK 0938 PM CDT TUE APR 25 2006 AREAS AFFECTED...FAR SRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 252... VALID 260238Z - 260415Z THREAT FOR SVR STORMS WILL LIKELY BE CONFINED TO AREAS ALONG THE LOWER RIO GRANDE RIVER VALLEY THROUGH THE NEXT FEW HRS WITH A MORE LIMITED THREAT ALONG THE IMMEDIATE FAR SOUTH TX COAST. GIVEN PRESENCE OF LARGE SCALE DIFFLUENT FLOW PATTERN ALOFT...CONVECTION WILL LIKELY CONTINUE WELL BEYOND WW 252 EXPIRATION TIME /04Z/. TRENDS WILL BE MONITORED...BUT A NEW WW IS NOT ANTICIPATED AFTER 04Z...ALTHOUGH LOCAL WFO EXTENSION OF WW 252 MAY OCCUR. 00Z BRO SOUNDINGS SHOWED A PRONOUNCED WARM LAYER CENTERED AROUND 850 MB...WITH TEMPERATURES 3-4 DEGREES WARMER IN THIS LAYER THAN ON THE 00Z CRP SOUNDING. RECENT RADAR TRENDS INDICATE THAT THIS LARGE AMT OF CINH WILL LIKELY KEEP THE ORGANIZED SVR THREAT WEST OF THE IMMEDIATE FAR SOUTH TX COAST. VERY HIGH INSTABILITY AND MODEST SHEAR WILL CONTINUE TO FAVOR SVR HAIL/WIND WITH THE STRONGEST STORMS OVER THE LOWER RIO GRANDE RIVER VALLEY AWAY FROM THE COAST. LOW LEVEL SHEAR HAS INCREASED RECENTLY PER THE BRO 88-D VWP DATA...AND THUS AN ISOLATED TORNADO THREAT WILL ALSO REMAIN POSSIBLE /ESPECIALLY WITH THE SUPERCELL STORM OVER ERN JIM HOGG AND WRN BROOKS COUNTIES/. ADDITIONAL SVR STORMS MAY CONTINUE TO DEVELOP ALONG THE SFC FRONT/OUTFLOW BOUNDARY INTERSECTION OVER THE NWRN 1/3RD OF WW 252 FOR THE NEXT SEVERAL HRS WHERE LOW LEVEL CONVERGENCE WILL BE MAXIMIZED. ..CROSBIE.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CRP...BRO... 25839955 27539957 27309685 25569686 WWWW From mcd at goshenarc.org Wed Apr 26 03:04:08 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 23:04:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260301 SWOMCD SPC MCD 260301 ALZ000-TNZ000-MSZ000-ARZ000-260400- MESOSCALE DISCUSSION 0662 NWS STORM PREDICTION CENTER NORMAN OK 1001 PM CDT TUE APR 25 2006 AREAS AFFECTED...NERN AR...WRN TN CONCERNING...SEVERE THUNDERSTORM WATCH 250... VALID 260301Z - 260400Z AFTER EARLIER INTENSE ACTIVITY...TSTMS NOW APPEAR TO BE WEAKENING RAPIDLY ACROSS REMAINING PORTIONS OF WW 250. HOWEVER...OTHER STORMS WERE BEGINNING TO DEVELOP ALONG THE COLD FRONT...NOW MOVING INTO INSTABILITY AXIS ACROSS ERN AR. WHILE A FEW STRONG STORMS COULD ACCOMPANY THE FRONTAL PASSAGE THROUGH LATE TONIGHT...AN ADDITIONAL WATCH IS NOT CURRENTLY PLANNED IN THE REGION. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...HUN...MEG... 34988915 34889041 35309045 35948963 35868812 34968800 WWWW From mcd at goshenarc.org Wed Apr 26 04:45:48 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 00:45:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260443 SWOMCD SPC MCD 260442 LAZ000-ARZ000-TXZ000-260545- MESOSCALE DISCUSSION 0663 NWS STORM PREDICTION CENTER NORMAN OK 1142 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TX...LA CONCERNING...SEVERE THUNDERSTORM WATCH 253... VALID 260442Z - 260545Z STORMS CONTINUE TO INCREASE ALONG COLD FRONT MOVING SLOWLY ACROSS LA AND THE UPPER TX COAST LATE TONIGHT. MOIST AND MARGINALLY UNSTABLE CONDITIONS IN POST-MCS AIR MASS ACROSS LA SHOULD CONTINUE TO SUPPORT MODEST/STRONG UPDRAFTS GIVEN PERSISTENT LIFT ALONG THE ADVANCING FRONTAL CIRCULATION. ADEQUATE DEEP SHEAR OF 30-45KT OBSERVED ON WINFIELD AND DE QUEEN WIND PROFILERS SUGGESTS THAT SUPERCELL STRUCTURE REMAINS A POSSIBILITY WITH THIS CONVECTION. A COUPLE OF HAIL/WIND EVENTS COULD OCCUR AS ACTIVITY DEVELOPS SLOWLY EAST TOWARD THE MS RIVER THROUGH THE NIGHT. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LCH...SHV...HGX... 29219222 29379373 29089494 28939533 30199470 31929459 32459403 33069340 33049197 32209190 30769220 WWWW From mcd at goshenarc.org Wed Apr 26 05:00:11 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 01:00:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260457 SWOMCD SPC MCD 260457 TXZ000-260630- MESOSCALE DISCUSSION 0664 NWS STORM PREDICTION CENTER NORMAN OK 1157 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 260457Z - 260630Z MARGINAL SEVERE HAIL POTENTIAL MAY BE INCREASING ACROSS PORTIONS OF SERN/SCNTRL TX EARLY TODAY. PERSISTENT ISENTROPIC LIFT ATOP LOW LEVEL FRONTAL INVERSION IS APPARENTLY ADEQUATE FOR PARCELS TO AGAIN REACH AN LFC ABOVE 850MB ACROSS SERN/SCNTRL TX LATE TONIGHT. BAND OF ELEVATED STORMS WAS NOW INCREASING ALONG THE ELEVATED FRONTAL SURFACE...GENERALLY ALONG A LINE FROM HDO TO AUS TO CLL. LATEST RUC SOUNDINGS FROM THE REGION INDICATED MUCAPE OF AROUND 1000 J/KG AVAILABLE TO THIS NEW ROUND OF STORMS. STRONG CLOUD BEARING SHEAR OF 40-60KT FURTHER SUPPORTS UPDRAFT INTENSIFICATION AND PERSISTENCE. UNCERTAINTY EXISTS REGARDING LARGE SCALE SUPPORT FOR STRONGER UPWARD MOTION ACROSS THE REGION...AND EXTENT OF SEVERE STORM COVERAGE. ADDITIONALLY...WITH SEVERE THREAT LIKELY CONFINED TO MARGINALLY SEVERE HAIL OF ABOUT AN INCH OR SO...CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...EWX... 30339555 29379839 29489955 30259884 31159636 31389544 31229523 WWWW From mcd at goshenarc.org Wed Apr 26 06:26:41 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 02:26:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260624 SWOMCD SPC MCD 260623 ALZ000-MSZ000-LAZ000-ARZ000-260830- MESOSCALE DISCUSSION 0665 NWS STORM PREDICTION CENTER NORMAN OK 0123 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS ERN LA...NRN AL...MUCH OF MS. CONCERNING...CONVECTIVE TRENDS VALID 260623Z - 260830Z GEN TSTM POTENTIAL WILL INCREASE ACROSS CORRIDOR FROM NRN AL TO SWRN MS THROUGH AT LEAST 9Z. MOST OF THIS ACTIVITY SHOULD REMAIN BELOW SEVERE LIMITS...HOWEVER OCCASIONAL DAMAGING GUSTS AND MRGLLY SEVERE HAIL ARE POSSIBLE. WW NOT ANTICIPATED ATTM. CONVECTION ACROSS THIS REGION WILL OCCUR IN ASSOCIATION WITH LOOSELY ORGANIZED TSTM COMPLEXES NOW MOVING ESEWD FROM SWRN TN AND NWRN MS TOWARD N-CENTRAL AL...AS WELL AS MOVING EWD FROM WW 253 ACROSS MS RIVER FROM ERN LA INTO WRN MS. ADDITIONAL DEVELOPMENT ALSO IS POSSIBLE ACROSS THIS REGION. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY FROM EARLIER MCS FROM FL PANHANDLE INTO NRN GULF...THEN NWWD ACROSS EXTREME SE TX AND EXTREME SWRN LA. NRN PORTION OF MCS-OVERTURNED AIR ALOFT APPEARS TO LIE NEAR BHM-GWO LINE. MODIFIED RAOBS AND RUC SOUNDINGS INDICATE ELEVATED MUCAPES AROUND 500 J/KG ACROSS PORTIONS CENTRAL/SRN MS...TRENDING UPWARD TO 1500-2000 J/KG RANGE WITH NRN EXTENT INTO NRN PORTIONS MS/AL WHERE EARLIER MCS DID NOT AFFECT AIR MASS ALOFT AS MUCH. GIVEN STEEPER LAPSE RATES OVER NRN PORTIONS MS/AL...AND SOMEWHAT LARGER EFFECTIVE SHEAR PROFILES WITH NRN EXTENT...HAIL POTENTIAL WILL BE LARGER WITH ACTIVITY IN THOSE AREAS THAN WITH COMPLEX MOVING EWD FROM LA. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN...MEG...JAN...LIX...LCH...SHV... 30789212 32159205 33189157 34479009 34958867 35008789 34818642 34218633 33908677 33728787 33028895 31488921 30469129 30359214 WWWW From mcd at goshenarc.org Wed Apr 26 08:14:42 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:14:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260811 SWOMCD SPC MCD 260811 LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0311 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SW TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260811Z - 260945Z THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650 WWWW From mcd at goshenarc.org Wed Apr 26 08:22:50 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:22:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260820 SWOMCD SPC MCD 260819 COR LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0319 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260819Z - 260945Z CORRECTED FOR TYPO THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650 WWWW From mcd at goshenarc.org Wed Apr 26 08:22:56 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:22:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260811 SWOMCD SPC MCD 260811 LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0311 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SW TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260811Z - 260945Z THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650  From mcd at goshenarc.org Wed Apr 26 08:26:06 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:26:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260820 SWOMCD SPC MCD 260819 COR LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0319 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260819Z - 260945Z CORRECTED FOR TYPO THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650  From mcd at goshenarc.org Wed Apr 26 11:08:57 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 07:08:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261106 SWOMCD SPC MCD 261105 TXZ000-261200- MESOSCALE DISCUSSION 0667 NWS STORM PREDICTION CENTER NORMAN OK 0605 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX. CONCERNING...SEVERE THUNDERSTORM WATCH 254... VALID 261105Z - 261200Z SEVERE TSTM POTENTIAL IS DIMINISHING ACROSS WW AREA. SOME OR ALL OF WW MAY BE CANCELLED BEFORE SCHEDULED 12Z EXPIRATION...OTHERWISE WW WILL BE ALLOWED TO EXPIRE WITHOUT FURTHER ISSUANCE. VWP/PROFILER DATA INDICATES SUBTLE MIDLEVEL SHORTWAVE TROUGH AND SPEED MAX CLOSELY CORRESPONDS TO WRN EDGE OF MOST CONCENTRATED PRECIP...AND IS APCHG SABINE RIVER ATTM. MEANWHILE...STABLE/POST-FRONTAL BOUNDARY LAYER CONTINUES TO DEEPEN ACROSS REGION. MAJORITY OF CONVECTION HAS MOVED/DEVELOPED EWD ACROSS LA...OUT OF AREA OF OPTIMAL COMBINED INSTABILITY/SHEAR PROFILES THAT STILL LINGER OVER PORTIONS S TX...BASED ON MODIFIED RAOBS AND RUC SOUNDINGS. ELEVATED BUOYANCY REMAINS FAVORABLE OVER REGION...AND EFFECTIVE SHEAR GENERALLY STRENGTHENS WITH WWD EXTENT. OCCASIONAL TSTM FORMATION AND POTENTIAL FOR MRGLLY SEVERE HAIL MAY LINGER WELL N OF FRONT...GENERALLY E OF I-45 AND NEAR NRN EDGE OF ORIGINAL WW. HOWEVER...APPARENT LACK OF ELEVATED ASCENT BEHIND MIDLEVEL PERTURBATION INDICATES LOW PROBABILITY FOR ADDITIONAL/ORGANIZED DEVELOPMENT BEFORE WW EXPIRES. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...SHV...HGX... 30889623 30919564 31369494 30749461 29869436 29859493 30099510 30019530 30099550 30079581 30209584 30219612 30409610 WWWW From mcd at goshenarc.org Wed Apr 26 15:07:14 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 11:07:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261504 SWOMCD SPC MCD 261504 SCZ000-GAZ000-261630- MESOSCALE DISCUSSION 0668 NWS STORM PREDICTION CENTER NORMAN OK 1004 AM CDT WED APR 26 2006 AREAS AFFECTED...NERN GA INTO WRN SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261504Z - 261630Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT. A WW LIKELY WILL BE NEEDED IN THE LEE OF THE SOUTHERN APPALACHIANS... PERHAPS BY EARLY AFTERNOON. INITIATION OF NEW CONVECTIVE DEVELOPMENT IS ALREADY UNDERWAY ACROSS THE HIGHER TERRAIN OF WESTERN SOUTH CAROLINA. THIS IS PROBABLY LARGELY DRIVEN BY OROGRAPHIC FORCING...BUT STRENGTHENING DIVERGENCE ALOFT...AHEAD OF SHORT WAVE TROUGH DIGGING FROM THE MIDDLE MISSISSIPPI VALLEY INTO THE TENNESSEE VALLEY...WILL COME OF INCREASING INFLUENCE THROUGH MID DAY. STORMS ARE EXPECTED TO INCREASE IN COVERAGE TO THE LEE OF THE APPALACHIANS THROUGH 16-18Z...ACROSS MUCH OF NORTHEAST GEORGIA INTO WESTERN SOUTH CAROLINA...WHERE MOIST BOUNDARY LAYER WILL CONTINUE TO DESTABILIZE WITH INSOLATION. MOST UNSTABLE CAPE IS ALREADY IN EXCESS OF 1500 J/KG...IN FAVORABLY SHEARED REGIME BENEATH 40+ KT WESTERLY MID-LEVEL FLOW...WHICH SHOULD BE SUFFICIENT FOR AT LEAST BRIEF MID-LEVEL UPDRAFT ROTATION. LARGE HAIL IS EXPECTED TO BE PRIMARY SEVERE THREAT THOUGH EARLY AFTERNOON...BEFORE DAMAGING WIND POTENTIAL INCREASES TO THE EAST SOUTHEAST LATER ON. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...GSP...FFC... 34428359 34598298 35058181 34748066 34018069 33238239 33338323 33888408 34198424 WWWW From mcd at goshenarc.org Wed Apr 26 16:05:49 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 12:05:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261602 SWOMCD SPC MCD 261602 GAZ000-FLZ000-261730- MESOSCALE DISCUSSION 0669 NWS STORM PREDICTION CENTER NORMAN OK 1102 AM CDT WED APR 26 2006 AREAS AFFECTED...NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261602Z - 261730Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT AND POSSIBILITY OF A WW. COLD POOL ASSOCIATED WITH MESOSCALE CONVECTIVE SYSTEM HAS OVERSPREAD MUCH OF SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI INTO THE WESTERN FLORIDA PANHANDLE...WITH STRONGEST PORTION SURGING SOUTHEAST OF THE LOUISIANA COAST. HOWEVER...MORE VIGOROUS CLUSTER OF STORMS ...NOW DEVELOPING EAST OF MOBILE...REMAINS IN CLOSE PROXIMITY TO COASTAL AREAS...AND APPEARS SUPPORTED BY FORCING ASSOCIATED WITH IMPULSE EMBEDDED WITHIN STRONGER MID/UPPER STREAM OF FLOW ALONG GULF COASTAL AREAS. MODELS SUGGEST THIS FORCING WILL GRADUALLY SHIFT EAST THROUGH THE FLORIDA BIG BEND REGION BY THE 20-21Z TIME FRAME. SURFACE DEW POINTS ACROSS THE FLORIDA BIG BEND/EASTERN PANHANDLE... INCLUDING THE TALLAHASSEE AREA...TO THE SOUTH OF AN OLD CONVECTIVE BOUNDARY WHICH EXTENDS THROUGH THE VALDOSTA/SAVANNAH GEORGIA AREAS ...ARE AROUND 70F. THIS IS CONTRIBUTING TO MIXED LAYER CAPE OF 1000 TO 2000 WITH INSOLATION...WHICH SEEMS LIKELY TO MAINTAIN VIGOROUS CONVECTIVE DEVELOPMENT INTO AND THROUGH THE AFTERNOON HOURS. HIGH PRECIPITABLE WATER CONTENT AIR /AROUND 2 INCHES/ FEEDING INTO CONVECTION WILL SUPPORT VERY HEAVY RAINFALL...BUT LOW HUMIDITIES AT MID LEVELS WILL ENHANCE EVAPORATIVE COOLING IN DOWNDRAFTS...AND ADDITIONAL SIGNIFICANT COLD POOLS APPEAR POSSIBLE. MODELS SUGGEST THAT A WESTERLY LOW-LEVEL JET WILL STRENGTHEN ACROSS NORTHERN FLORIDA WITH APPROACH OF UPPER IMPULSE. AS THIS OCCURS...FORWARD PROPAGATION OF ANY COLD POOLS WILL BE ENHANCED...ALONG WITH RISK OF DAMAGING WINDS. THIS SEEMS POSSIBLE NEAR/EAST OF TALLAHASSEE THROUGH THE JACKSONVILLE AREAS DURING THE 18-21Z TIME FRAME. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...TBW...JAX...TAE... 31708067 30498072 30038121 29678215 29088320 28798544 29968549 30878492 31298410 31258269 31638168 31838116 WWWW From mcd at goshenarc.org Wed Apr 26 18:19:42 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 14:19:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261817 SWOMCD SPC MCD 261816 SCZ000-GAZ000-261945- MESOSCALE DISCUSSION 0670 NWS STORM PREDICTION CENTER NORMAN OK 0116 PM CDT WED APR 26 2006 AREAS AFFECTED...SOUTH CAROLINA AND PARTS OF EASTERN GEORGIA CONCERNING...SEVERE THUNDERSTORM WATCH 255... VALID 261816Z - 261945Z CONTINUE WW. SCATTERED INTENSE CONVECTIVE DEVELOPMENT IS ONGOING FROM THE LEE OF THE SOUTHERN APPALACHIANS INTO THE SOUTH CAROLINA PIEDMONT. THIS IS GENERALLY ALONG/SOUTH OF SURFACE FRONTAL ZONE EXTENDING FROM UPSTATE SOUTH CAROLINA THROUGH AREAS NEAR/NORTH OF COLUMBIA INTO THE VICINITY OF MYRTLE BEACH. WEAK SURFACE LOW NEAR COLUMBIA IS PROVIDING A FOCUS FOR STRONGER LOW-LEVEL CONVERGENCE...AND CONSOLIDATION OF ACTIVITY INTO A MORE SUBSTANTIAL CONVECTIVE CLUSTER APPEARS POSSIBLE ACROSS THE CENTRAL SOUTH CAROLINA PIEDMONT THROUGH 21Z. OBJECTIVE ANALYSIS INDICATES MIXED LAYER CAPE IN WARM SECTOR OF LOW IS ON THE ORDER OF 2000 J/KG. AS CONVECTION BEGINS TO INGEST THIS AIR MASS...INTENSIFYING UPDRAFTS IN SUFFICIENTLY SHEARED ENVIRONMENT FOR SUPERCELLS COULD BECOME SUPPORTIVE OF ISOLATED VERY LARGE HAIL NEAR COLUMBIA. THROUGH LOW-LEVEL HODOGRAPHS ARE GENERALLY SMALL/WEAK...AN ISOLATED TORNADO IS POSSIBLE...BEFORE DAMAGING WIND THREAT INCREASES TOWARD THE COASTAL PLAIN LATER THIS AFTERNOON. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILM...CHS...CAE...GSP... 34098097 34238061 33737979 33527977 33008017 33168082 33258133 33238174 33888237 34008182 WWWW From mcd at goshenarc.org Wed Apr 26 19:09:17 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 15:09:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261906 SWOMCD SPC MCD 261905 GAZ000-ALZ000-TNZ000-MSZ000-262100- MESOSCALE DISCUSSION 0671 NWS STORM PREDICTION CENTER NORMAN OK 0205 PM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS OF ERN MS/MOST OF AL/FAR NW GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261905Z - 262100Z SCATTERED THUNDERSTORM CLUSTERS WILL MOVE EWD FROM NRN AL TOWARDS WW 255. ADDITIONAL DEVELOPMENT MAY OCCUR FURTHER S ALONG COLD FRONT ACROSS ERN MS INTO CNTRL/SRN AL. MARGINAL LAPSE RATES AND OVERALL LACK OF INSTABILITY WILL LIMIT THE LARGE HAIL THREAT. A WW IS NOT ANTICIPATED. A SMALL AREA OF CLEARING BEHIND MORNING CONVECTION AND AHEAD OF SYNOPTIC COLD FRONT HAS LED TO SCATTERED THUNDERSTORM DEVELOPMENT ACROSS PORTIONS OF NRN AL. MODIFIED 12Z RAOBS AND RUC SOUNDINGS INDICATE A WEAKLY UNSTABLE ENVIRONMENT WITH MLCAPES OF 500 TO 800 J/KG. EFFECTIVE SHEAR AROUND 40 KTS WOULD SUPPORT UPDRAFT ORGANIZATION. HOWEVER...MARGINAL MID-LEVEL LAPSE RATES WILL LIKELY LIMIT THE LARGE HAIL THREAT. FURTHER S INTO PORTIONS OF ERN MS AND CNTRL/SRN AL...ADDITIONAL DESTABILIZATION WILL TAKE PLACE IN THE NEAR TERM WITH CONVECTIVE DEBRIS FROM GULF COAST MCS MOVING E OF AREA. THIS SHOULD ALLOW MLCAPES TO REACH AROUND 500 J/KG. WITH APPROACH OF THE COLD FRONT...CONVECTIVE DEVELOPMENT MAY OCCUR. HOWEVER...THE LINGERING EFFECTS OF THE MORNING MCS WILL KEEP MARGINAL MID-LEVEL LAPSE RATES INTACT AND MITIGATE THE LARGE HAIL THREAT. ..GRAMS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...BMX...HUN...MOB...JAN... 31718980 33208837 34298703 35018590 34908455 34218453 33368504 32068634 31188744 31238901 WWWW From mcd at goshenarc.org Wed Apr 26 19:41:58 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 15:41:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261938 SWOMCD SPC MCD 261938 GAZ000-FLZ000-262115- MESOSCALE DISCUSSION 0672 NWS STORM PREDICTION CENTER NORMAN OK 0238 PM CDT WED APR 26 2006 AREAS AFFECTED...SW GA...NE FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261938Z - 262115Z SEVERE THREAT SOUTH OF WW 255 SEEMS LIKELY TO REMAIN ISOLATED... LIMITED TO AREAS SOUTHWEST THROUGH SOUTH OF JACKSONVILLE. AN ADDITIONAL WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED. LATEST RUC SUGGESTS 30 TO 35 KT SOUTHWESTERLY LOW-LEVEL JET MAY BE DEVELOPING ACROSS THE FLORIDA BIG BEND THROUGH SOUTHERN GEORGIA... MUCH AS EARLIER PROGGED BY NAM/GFS. THIS SEEMS TO BE ENHANCING EASTWARD PROPAGATION OF CONVECTIVELY GENERATED SURFACE COLD POOL WHICH IS PROGRESSING EAST OF THE ALBANY/VALDOSTA/TALLAHASSEE AREAS. DIVERGENT WEAK WESTERLY SURFACE FLOW AHEAD OF COLD POOL IS LIMITING STRENGTH OF UPLIFT ALONG GUST FRONT...WHICH LIKELY WILL PRECLUDE EVOLUTION OF A LARGER CONVECTIVE CLUSTER. MOST SIGNIFICANT CONVECTION SEEMS LIKELY TO CONTINUE TO DEVELOP NORTH/EAST OF BRUNSWICK INTO THE SAVANNAH RIVER VALLEY. HOWEVER...ADDITIONAL NEW VIGOROUS THUNDERSTORM ACTIVITY STILL APPEARS POSSIBLE...AS GUST FRONT PROGRESSES INTO AREAS SOUTHWEST THROUGH SOUTH OF JACKSONVILLE. THIS IS WHERE LOW-LEVEL LAPSE RATES REMAIN STEEPEST...PROVIDING A FAVORABLE ENVIRONMENT FOR STRONG WIND GUSTS...PERHAPS SOME MARGINALLY SEVERE HAIL. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...TBW...JAX...TAE... 31678271 31808224 31798148 31068110 30348114 29648199 29228290 29098371 29148439 29798411 30218335 WWWW From Mcd at goshenarc.org Fri Apr 28 12:03:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 08:03:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281203 SWOMCD SPC MCD 281203 KSZ000-OKZ000-TXZ000-COZ000-NMZ000-281400- MESOSCALE DISCUSSION 0675 NWS STORM PREDICTION CENTER NORMAN OK 0703 AM CDT FRI APR 28 2006 AREAS AFFECTED...NERN NM ACROSS THE TX/OK PNHDLS...SWRN AND CNTRL KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281203Z - 281400Z TSTMS ARE EXPECTED TO BECOME MORE NUMEROUS AND STRONGER IN THE NEXT FEW HOURS FROM NERN NM EWD AND NEWD ACROSS PORTIONS OF THE OK/TX PNHDLS...AND INTO KS. SOME OF THESE STORMS WILL LIKELY PRODUCE HAIL. WHILE IT DOES NOT APPEAR IMMINENT...A WATCH MIGHT BE NEEDED FOR SOME OF THESE AREAS THIS MORNING. ELEVATED CONVECTION WAS ON THE INCREASE FROM THE SRN HIGH PLAINS TO THE SCNTRL PLAINS THIS MORNING AS A PAIR OF UPPER LEVEL SHORT WAVE TROUGHS BEGIN TO IMPOSE STRONGER LARGE SCALE ASCENT OVER THE REGION. AS A NRN STREAM IMPULSE DIGS SEWD ACROSS CO...A STRONG SRN STREAM UPPER LOW WAS DEVELOPING EAST FROM THE AZ/NM BORDER. THE MID/UPPER LEVEL DIFFLUENT FLOW AHEAD OF THE SRN SYSTEM HAS ENHANCED THE NOCTURNAL LOW LEVEL JET AND AIDED MOISTURE TRANSPORT NWD INTO A SW-NE ORIENTED DEFORMATION AXIS SITUATED FROM NM NEWD ACROSS KS. CONTINUED STRENGTHENING OF UPWARD MOTION/DPVA ASSOCIATED WITH THE NRN STREAM TROUGH...AND LARGE SCALE UPPER JET COUPLING BETWEEN THE NRN AND SRN SYSTEMS...SHOULD MAINTAIN A FAVORABLE ENVIRONMENT FOR INCREASINGLY WIDESPREAD CONVECTION THROUGH THE MORNING. DESPITE RECENT UPWARD TREND IN STORM COVERAGE ACROSS KS AND PRESENCE OF MODEST LAPSE RATES OF 7-8 C/KM...EFFECTIVE SHEAR ACROSS PARTS OF THE AREA APPEARS SOMEWHAT LIMITED WITHIN DEVELOPING MID LEVEL DEFORMATION ZONE BETWEEN NRN AND SRN STREAM SYSTEMS. HOWEVER... STEEPER LAPSE RATES...STRONGER SHEAR AND FORCING ARE FORECAST TO OVERSPREAD NM...TX/OK PNHDLS...AND SWRN KS AREAS THROUGH THE MORNING. MORE INTENSE CONVECTION...POSSIBLY IN THE FORM OF A FEW ELEVATED SUPERCELLS WITH PERSISTENT STORM UPDRAFTS AND LARGE HAIL...COULD DEVELOP IN THESE AREAS. A SEVERE TSTM WATCH MAY BE NEEDED AS ACTIVITY DEVELOPS THROUGH THE MORNING. ..CARBIN.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TOP...ICT...OUN...GID...DDC...GLD...AMA...PUB...ABQ... 36349959 35100268 35460410 36460406 37170182 38820085 39589834 39259703 38369687 WWWW From Mcd at goshenarc.org Fri Apr 28 15:24:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 11:24:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281524 SWOMCD SPC MCD 281523 OKZ000-TXZ000-281700- MESOSCALE DISCUSSION 0676 NWS STORM PREDICTION CENTER NORMAN OK 1023 AM CDT FRI APR 28 2006 AREAS AFFECTED...ERN TX PNHDL...WRN OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281523Z - 281700Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT AND POSSIBILITY OF A WW. NEW CONVECTIVE DEVELOPMENT IS EXPECTED ACROSS THE EASTERN TEXAS PANHANDLE AND PARTS OF WESTERN OKLAHOMA THROUGH THE 17-19Z TIME FRAME. THIS SEEMS LIKELY TO OCCUR IN ASSOCIATION WITH STRONGER MID-LEVEL COOLING/ASCENT IN EXIT REGION OF 70+ KT CYCLONIC 500 MB JET STREAK...WHICH CONTINUES TO SLOWLY NOSE INTO SOUTHWEST TEXAS. MID-LEVEL LAPSE RATES ARE ALREADY RATHER STEEP AND...WITH FURTHER DESTABILIZATION...MOST UNSTABLE CAPE FOR MOIST PARCELS ABOVE LINGERING NEAR SURFACE INVERSION LAYER MAY APPROACH 2000 J/KG. SHEAR PROFILES IN CLOUD BEARING LAYER APPEAR SUPPORTIVE OF MID- LEVEL UPDRAFT ROTATION...WHICH SHOULD ENHANCE POTENTIAL FOR LARGE HAIL IN STRONGER STORMS. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...LUB...AMA... 35740108 36420043 36519957 35549887 33849909 33300064 34400082 35090117 WWWW From Mcd at goshenarc.org Fri Apr 28 15:44:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 11:44:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281543 SWOMCD SPC MCD 281543 TXZ000-281715- MESOSCALE DISCUSSION 0677 NWS STORM PREDICTION CENTER NORMAN OK 1043 AM CDT FRI APR 28 2006 AREAS AFFECTED...TEXAS SOUTH PLAINS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281543Z - 281715Z A TORNADO WATCH WILL LIKELY BE NEEDED...POSSIBLY BEFORE NOON. TIMING OF INITIATION OF SURFACE-BASED CONVECTIVE DEVELOPMENT IS A BIT UNCERTAIN. HOWEVER..LATEST OBJECTIVE ANALYSIS SUGGESTS INHIBITION HAS BECOME RATHER WEAK NEAR/JUST AHEAD OF DRY LINE...FROM THE LUBBOCK AREA SOUTHWARD TO NEAR SAN ANGELO...WHERE MIXED LAYER CAPE IS ON THE ORDER OF 1500 J/KG. FURTHER DESTABILIZATION WILL OCCUR WITH CONTINUING INSOLATION...AND A GRADUAL MID-LEVEL COOLING AS MID/UPPER JET NOSES ACROSS WEST TEXAS. A 30+ KT SOUTHERLY LOW-LEVEL JET IS CONTRIBUTING TO SHEAR PROFILES EASILY SUFFICIENT FOR SUPERCELLS...WHICH COULD FORM AS EARLY AS 17-18Z. LATEST TRENDS IN SATELLITE IMAGERY SUGGEST THIS IS MOST LIKELY JUST TO THE SOUTHEAST OF LUBBOCK. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SJT...LUB...MAF... 33750182 33530079 32980042 32240067 31360115 31290199 32080193 32800219 WWWW From Mcd at goshenarc.org Fri Apr 28 18:04:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 14:04:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281804 SWOMCD SPC MCD 281804 OKZ000-TXZ000-281930- MESOSCALE DISCUSSION 0679 NWS STORM PREDICTION CENTER NORMAN OK 0104 PM CDT FRI APR 28 2006 AREAS AFFECTED...N CNTRL TX THRU S CNTRL/SE OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281804Z - 281930Z TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN ADDITIONAL WW EAST OF WW 256. WHILE SURFACE-BASED CONVECTIVE INITIATION APPEARS UNDERWAY ALONG DRY LINE...SOUTHEAST OF LUBBOCK THROUGH AREAS EAST/SOUTHEAST OF MIDLAND...AN INCREASE IN CONVECTIVE DEVELOPMENT IS ALSO ONGOING NORTH OF THE TEXAS HILL COUNTRY INTO AREAS NEAR/WEST OF DALLAS/FORT WORTH. THIS APPEARS BASED ABOVE AT LEAST SHALLOW NEAR SURFACE INVERSION LAYER...IN ASSOCIATION WITH BROADER AREA OF ISENTROPIC ASCENT... DOWNSTREAM OF SOUTHERN PLATEAU CLOSED LOW. THIS FORCING WILL SPREAD NORTHEASTWARD ACROSS THE RED RIVER VALLEY THROUGH THE 20-21Z TIME FRAME...AS UPPER SYSTEM SHIFTS INTO THE SOUTHERN ROCKIES. STEEP MID-LEVEL LAPSE RATES ARE CONTRIBUTING TO MOST UNSTABLE CAPE ON THE ORDER OF 1000 J/KG OVER A FAIRLY BROAD AREA OF THE SOUTHERN PLAINS. THIS WILL SUPPORT RISK OF LARGE HAIL IN STRONGEST CELLS...THOUGH INCREASINGLY WIDESPREAD NATURE OF CONVECTION MAY TEND TO MITIGATE THREAT MOST AREAS NORTH/EAST OF DALLAS/FORT WORTH. BEST HAIL POTENTIAL SEEMS LIKELY TO REMAIN CONFINED TO AREAS WEST OF THE METROPLEX INTO THE EDWARDS PLATEAU...IN CLOSER PROXIMITY STEEPENING LOW-LEVEL LAPSE RATES. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT... 32009985 33419856 34069811 34639740 34709621 34359515 33719492 32009692 31089794 30869953 WWWW From Mcd at goshenarc.org Sat Apr 29 01:44:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 21:44:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290144 SWOMCD SPC MCD 290144 OKZ000-TXZ000-290315- MESOSCALE DISCUSSION 0686 NWS STORM PREDICTION CENTER NORMAN OK 0844 PM CDT FRI APR 28 2006 AREAS AFFECTED...SOUTHERN OK...NORTH CENTRAL TX CONCERNING...TORNADO WATCH 258... VALID 290144Z - 290315Z ...SEVERE THREAT IS INCREASING ACROSS THE METROPLEX... COMPLEX PATTERN HAS EVOLVED ACROSS NORTH CENTRAL TX INTO THE RED RIVER REGION OF SRN OK THIS EVENING. STRENGTHENING WARM ADVECTION BENEATH LLJ APPEARS TO BE PARTLY RESPONSIBLE FOR EXPANDING SEVERE CLUSTERS ALONG THE RED RIVER...TRAILING SWWD INTO STEPHENS COUNTY TX. ONE LONG LIVED DESTRUCTIVE SUPERCELL OVER GRAYSON COUNTY TX SEEMS TO HAVE BEEN ENHANCED BY STRONG LOW LEVEL SHEAR ALONG RETREATING BOUNDARY THAT IS LOSING IDENTITY OVER NERN TX. RECENT TRENDS SUGGEST AN UPWARD EXPANSION OF ACTIVITY FROM WEST-NORTH OF THE METROPLEX. THIS CONVECTION WILL SPREAD ACROSS THE REMAINDER OF NORTH CENTRAL TX LATER THIS EVENING INTO THE EARLY MORNING HOURS. ADDITIONAL THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG ADVANCING COLD FRONT AS IT SWEEPS SEWD LATER TONIGHT. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...FWD...OUN... 34199808 34449553 33629538 33399626 32979682 32339750 32339892 WWWW From Mcd at goshenarc.org Sat Apr 29 03:03:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 23:03:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290303 SWOMCD SPC MCD 290303 TXZ000-290430- MESOSCALE DISCUSSION 0687 NWS STORM PREDICTION CENTER NORMAN OK 1003 PM CDT FRI APR 28 2006 AREAS AFFECTED...EAST TX CONCERNING...TORNADO WATCH 258...259... VALID 290303Z - 290430Z ...SEVERE THREAT WILL INCREASE EAST OF WATCHES 258/259 ACROSS EAST TX BY THE EARLY MORNING HOURS. TORNADO WATCH WILL BE ISSUED BY MIDNIGHT... COLD FRONT CONTINUES TO SURGE SWD ACROSS THE TX HIGH PLAINS WHILE WARM ADVECTION APPEARS TO BE THE PRIMARY AGENT IN SEVERE THUNDERSTORM CLUSTERS FROM NEAR THE RED RIVER...SWD INTO THE HILL COUNTRY. AS LARGE SCALE FORCING SPREADS ACROSS CNTRL TX CONVECTION SHOULD BEGIN TO DEVELOP NEAR THE ERN EDGE OF TORNADO WATCHES...BENEATH STRONG LLJ. LATEST THINKING IS SEVERE THUNDERSTORM CLUSTERS OVER THE HILL COUNTRY...AND OVER THE DFW METROPLEX WILL BE APPROACHING THE ERN EDGE OF TORNADO WATCHES BY MIDNIGHT. GIVEN THE STRONG LOW LEVEL SHEAR...40KT SFC-1KM/HELICITY...500-700M2/S2...NEW TORNADO WATCH WILL BE ISSUED DOWNSTREAM TO ACCOUNT FOR THIS EVOLUTION. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX... 30039740 33589625 33109433 30049552 WWWW From Mcd at goshenarc.org Sat Apr 29 04:15:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 29 Apr 2006 00:15:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290414 SWOMCD SPC MCD 290414 TXZ000-290545- MESOSCALE DISCUSSION 0688 NWS STORM PREDICTION CENTER NORMAN OK 1114 PM CDT FRI APR 28 2006 AREAS AFFECTED...SOUTH CENTRAL TX CONCERNING...TORNADO WATCH 259... VALID 290414Z - 290545Z ...SEVERE THREAT IS INCREASING ACROSS SOUTH CENTRAL TX...WW WILL LIKELY BE ISSUED JUST SOUTH OF WW259... LATEST DIAGNOSTIC DATA SUGGESTS LOW LEVEL CONVERGENCE WILL PROVE SUFFICIENT IN FORCING BOUNDARY LAYER PARCELS TO THEIR LFC ALONG ADVANCING WIND SHIFT. RADAR TRENDS SUPPORT THIS WITH SWWD DEVELOPMENT ALONG PRE-FRONTAL BOUNDARY INTO NERN MEXICO WEST OF DRT. FORECAST SOUNDINGS SUGGEST STRONG CAP JUST SOUTH OF CURRENT WW259 WILL BE REMOVED THROUGH VERTICAL ASCENT/COOLING. DEVELOPING SQUALL LINE WILL LIKELY ADVANCE INTO PORTIONS OF SOUTH CENTRAL TX NOT CURRENTLY COVERED BY TORNADO WATCH. FOR THIS REASON WILL LIKELY ISSUE ANOTHER SMALL WATCH TO ACCOUNT FOR THIS EVOLUTION. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 30230053 30109845 29209826 28679926 29120077 WWWW From MCD at goshenarc.org Sat Apr 1 00:15:26 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 19:15:26 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010018 SWOMCD SPC MCD 010017 OHZ000-KYZ000-INZ000-010145- MESOSCALE DISCUSSION 0381 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CST FRI MAR 31 2006 AREAS AFFECTED...SERN LOWER MI...ERN THROUGH SRN IND AND WRN OH CONCERNING...TORNADO WATCH 117...118... VALID 010017Z - 010145Z THREAT FOR LARGE HAIL...ISOLATED STRONG WIND GUSTS AND ISOLATED TORNADOES PERSISTS ACROSS THE REMAINING PORTIONS OF WW 117 AND 118. STORMS WILL APPROACH THE ERN PORTION OF THE WATCHES BY 01Z. WW MAY BE NEEDED SOON FOR PARTS OF EXTREME SERN IND INTO WRN OH. EARLY THIS EVENING A SQUALL LINE EXTENDS FROM SERN LOWER MI SWWD THROUGH NWRN OH INTO CNTRL AND SWRN IND. THE LINE IS MOVING EAST AT AROUND 30 KT. STORMS ARE CURRENTLY MOVING THROUGH THE AXIS OF BEST INSTABILITY WITH MLCAPE FROM 500 TO 1000 J/KG. OBJECTIVE ANALYSIS INDICATES INSTABILITY IS MORE MARGINAL AND THE BOUNDARY LAYER MORE STABLE WITH EWD EXTENT INTO OH WHERE LESS HEATING OCCURRED TODAY. THIS COULD SERVE AS A LIMITING FACTOR AS STORMS MOVE EWD. HOWEVER...THETA-E ADVECTION ALONG THE STRONG SWLY LOW LEVEL JET MAY CONTRIBUTE TO SOME NEWD DESTABILIZATION INTO WRN OH THIS EVENING. VERTICAL SHEAR PROFILES WILL REMAIN SUFFICIENT TO SUPPORT ORGANIZED STORMS GIVEN SUFFICIENT DESTABILIZATION. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CLE...ILN...LMK...IWX...IND... 40708307 39118448 38918541 40138487 41638348 WWWW From MCD at goshenarc.org Sat Apr 1 01:28:21 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 20:28:21 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010131 SWOMCD SPC MCD 010130 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-010300- MESOSCALE DISCUSSION 0382 NWS STORM PREDICTION CENTER NORMAN OK 0730 PM CST FRI MAR 31 2006 AREAS AFFECTED...FAR ERN AR INTO TN AND NRN MS/AL/NWRN GA CONCERNING...TORNADO WATCH 119... VALID 010130Z - 010300Z SCATTERED THUNDERSTORMS...SOME SEVERE...WILL PERSIST FOR A COUPLE MORE HOURS...BUT AN ADDITIONAL WW IS NOT EXPECTED DUE TO DECREASING THREAT WITH TIME. SWLY FETCH OF RELATIVELY WARM/MOIST AIR CONTINUES TO FEED STORMS WITHIN WARM ADVECTION ZONE. AREA VAD WIND PROFILES AND PROFILER DATA INDICATE FAVORABLE HODOGRAPHS FOR SUPERCELLS...WITH MODERATELY STRONG LOW LEVEL SHEAR ESPECIALLY INTO MIDDLE TN. WITH TIME...LOW LEVEL JET WILL VEER AS UPPER SYSTEM SHIFTS NEWD...WHICH WILL DECREASE SHEAR PROFILES AND ALLOW FOR CONTINUED WARMING ALOFT. THIS...COMBINED WITH CESSATION OF SURFACE HEATING...WILL CAUSE A GRADUAL DECREASE IN STORM INTENSITY TO BELOW SEVERE LIMITS BY THE TIME WW 119 EXPIRES. THE THREAT HAS ALREADY ENDED OVER NWRN PORTIONS OF THE WATCH. ADDITIONAL DEVELOPMENT...MOST LIKELY SUB-SEVERE...IS EXPECTED ACROSS NRN MS AND AL WITHIN INSTABILITY AXIS. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN...LZK... 33399093 33639147 35659092 36258819 36518609 36498474 35388473 34098487 33508579 WWWW From MCD at goshenarc.org Sat Apr 1 02:27:54 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 21:27:54 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010227 SWOMCD SPC MCD 010226 INZ000-KYZ000-010330- MESOSCALE DISCUSSION 0383 NWS STORM PREDICTION CENTER NORMAN OK 0826 PM CST FRI MAR 31 2006 AREAS AFFECTED...SRN IND THROUGH NRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 118... VALID 010226Z - 010330Z TORNADO WATCH 118 WILL LIKELY BE ALLOWED TO EXPIRE AT 03Z. SEVERE THREAT MAY PERSIST A COUPLE HOURS BEYOND 03Z FOR A FEW COUNTIES IN SRN IND AND NRN KY...BUT A GRADUAL WEAKENING TREND IS EXPECTED LATER THIS EVENING. SQUALL LINE EXTENDS FROM WRN KY INTO SRN IND. THE LINE IS MOVING SEWD AT AROUND 20 KT. TREND HAS BEEN FOR STRONGER STORMS TO PERSIST ON THE SRN END OF THE LINE ACROSS SRN IND IN CLOSER PROXIMITY TO FEED OF HIGHER INSTABILITY WITH SBCAPE NEAR 1000 J/KG. VERTICAL SHEAR PROFILES WILL CONTINUE TO SUPPORT ORGANIZED STORM STRUCTURES WITHIN THE LINE. HOWEVER...AS THE BOUNDARY LAYER CONTINUES TO COOL AND THE LOW LEVEL FLOW VEERS...STORMS SHOULD BEGIN TO UNDERGO A GRADUAL DECREASE AFTER ANOTHER COUPLE HOURS. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...PAH... 38538505 37918583 37668708 38298729 38588627 38888527 WWWW From MCD at goshenarc.org Sat Apr 1 03:39:55 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 22:39:55 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010339 SWOMCD SPC MCD 010338 OHZ000-KYZ000-INZ000-010445- MESOSCALE DISCUSSION 0384 NWS STORM PREDICTION CENTER NORMAN OK 0938 PM CST FRI MAR 31 2006 AREAS AFFECTED...NRN KY...SWRN OH THROUGH EXTREME SERN IND CONCERNING...SEVERE THUNDERSTORM WATCH 120... VALID 010338Z - 010445Z SEVERE THREAT MAY PERSIST FOR ANOTHER 30 MIN IN REMAINING PORTION OF WW 120. BEYOND THIS TIME...ANY REMAINING SEVERE THREAT WILL LIKELY HAVE SHIFTED S OF WW 120 INTO PORTIONS OF EXTREME NRN KY BY 04Z. SQUALL LINE EXTENDS FROM SWRN OH SWWD THROUGH EXTREME NRN KY INTO SRN IND. THE LINE IS MOVING SEWD AT AROUND 20-25 KT. STRONGEST PORTION OF THE LINE CONTINUES TO PERSIST ALONG THE SWRN FLANKS IN PROXIMITY TO FEED OF BETTER INSTABILITY...WHILE STORMS ON THE NRN END WEAKEN WITH EWD EXTENT. OVERALL TREND SHOULD CONTINUE TO BE FOR STORMS TO GRADUALLY WEAKEN AS THE BOUNDARY LAYER STABILIZES AND THE LOW LEVEL FLOW VEERS. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK... 38688449 38958531 39368357 WWWW From MCD at goshenarc.org Sat Apr 1 04:22:14 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 31 Mar 2006 23:22:14 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010421 SWOMCD SPC MCD 010421 TXZ000-010545- MESOSCALE DISCUSSION 0385 NWS STORM PREDICTION CENTER NORMAN OK 1021 PM CST FRI MAR 31 2006 AREAS AFFECTED...WRN THROUGH NWRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 010421Z - 010545Z STRONGER STORMS DEVELOPING OVER NWRN TX MAY BE CAPABLE OF PRODUCING HAIL. CURRENT THINKING IS THAT COVERAGE WILL PROBABLY NOT BE SUFFICIENT TO WARRANT A WW AT THIS TIME...BUT TRENDS WILL CONTINUE TO BE MONITORED. LATE THIS EVENING A WARM FRONT EXTENDS FROM SERN OK SWWD THROUGH NWRN TX. WRN PORTION OF THIS BOUNDARY HAS BEGUN TO LIFT NWD DUE TO AN INCREASE IN SLY LOW LEVEL JET OF 25 TO 30 KT ASSOCIATED WITH DEVELOPING LEE TROUGH. THE WARM SECTOR S OF THE WARM FRONT IS MODERATELY UNSTABLE...AND THIS HIGHER THETA-E AIR WILL CONTINUE TO BE ADVECTED NWD OVERNIGHT. A FEW ELEVATED STORMS HAVE DEVELOPED OVER WRN TX JUST S OF LUBBOCK WITHIN ZONE OF ISENTROPIC ASCENT N OF THE WARM FRONT ASSOCIATED WITH THE MODEST LOW LEVEL JET. THE UPPER PATTERN IS CHARACTERIZED BY A BROAD UPPER LEVEL RIDGE WITH RELATIVELY WEAK FLOW ALOFT RESULTING IN VERTICAL SHEAR PROFILES SUPPORTIVE PRIMARILY OF MULTICELL CONVECTION. HOWEVER...STEEP MID LEVEL LAPSE RATES AND MODERATE MUCAPE SUGGEST A FEW UPDRAFTS MAY BE STRONG ENOUGH TO SUPPORT A THREAT FOR HAIL. LOW LEVEL JET IS RATHER BROAD AND IS FORECAST TO VEER WITH TIME. THIS SUGGESTS ADDITIONAL DEVELOPMENT FARTHER NE INTO NWRN TX MAY BE POSSIBLE. ..DIAL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 32620088 32420187 33590143 34129886 33619829 WWWW From MCD at goshenarc.org Sat Apr 1 07:08:33 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 02:08:33 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 010708 SWOMCD SPC MCD 010707 OKZ000-TXZ000-010930- MESOSCALE DISCUSSION 0386 NWS STORM PREDICTION CENTER NORMAN OK 0107 AM CST SAT APR 01 2006 AREAS AFFECTED...WRN N TX AND SWRN-SCNTRL OK CONCERNING...CONVECTIVE TRENDS VALID 010707Z - 010930Z TSTMS WITH MARGINALLY SEVERE HAIL WILL SPREAD ENEWD FROM WRN N TX INTO SWRN/SCNTRL OK THROUGH 12Z. WW IS NOT EXPECTED. EARLY MORNING SFC ANALYSIS PLACES A FRONT FROM SERN OK SWWD INTO THE TX S PLAINS. SLY 30-40 KT LLJ CONTINUES TO IMPINGE ON THIS BOUNDARY AND IS SUPPORTING ELEVATED MULTI-CELL TSTM CLUSTER OVER WRN N TX. AS THE LLJ VEERS THIS MORNING...TSTMS ARE APT TO MOVE/DEVELOP FARTHER N/NE ACROSS SWRN/SCNTRL OK THROUGH DAYBREAK. CLOUD-BEARING SHEAR IS NOT PARTICULARLY STRONG OWING TO CLOSE PROXIMITY OF THE UPPER RIDGE AXIS. BUT...PARCELS FEEDING THE TSTMS WILL BE EMANATING FROM STEEP LAPSE RATES...RESULTING IN STRONG TO MARGINALLY SEVERE PULSE-TYPE STORMS WITH HAIL. GIVEN THE MAGNITUDE OF DRY AIR BETWEEN THE NEAR-SFC INVERSION AND CLOUD BASE...GUSTY WINDS MAY OCCUR WITH THE STORMS AS WELL. GIVEN THE MARGINALITY OF HAIL SIZE AND SPATIAL COVERAGE...A WW IS NOT ANTICIPATED. ..RACY.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB... 34510051 34979900 35129706 34989644 34539623 33879634 33459757 33329861 33249961 33610007 WWWW From MCD at goshenarc.org Sat Apr 1 11:40:21 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 06:40:21 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011139 SWOMCD SPC MCD 011139 VTZ000-MAZ000-NYZ000-PAZ000-011415- MESOSCALE DISCUSSION 0387 NWS STORM PREDICTION CENTER NORMAN OK 0539 AM CST SAT APR 01 2006 AREAS AFFECTED...EXTREME NERN PA...CNTRL/ERN NY AND WRN NEW ENGLAND CONCERNING...CONVECTIVE TRENDS VALID 011139Z - 011415Z A LINE OF CONVECTION WILL PRODUCE GUSTY WINDS /ISOLD DAMAGING WINDS/ AND PERHAPS SMALL HAIL AS IT MOVES ACROSS EXTREME NERN PA...CNTRL/ERN NY AND WRN NEW ENGLAND THROUGH LATE MORNING. WW IS NOT EXPECTED. LEADING EDGE OF STRONG LARGE SCALE ASCENT ASSOCIATED WITH THE UPPER LEVEL LOW WAS SPREADING EWD ACROSS THE LWR GRTLKS REGION AT DAYBREAK PER WATER VAPOR IMAGERY. ASSOCIATED COLD FRONT HAS BECOME ACTIVE SINCE 09Z WITH A FORCED LINE OF LOW-TOPPED CONVECTION ACROSS WRN NY AND NCNTRL PA. THIS LINE SHOULD BE MAINTAINED AS IT TRANSLATES ENEWD AT 30-35 KTS INTO CNTRL/ERN NY AND NERN PA BETWEEN 13-16Z AND INTO WRN NEW ENGLAND BY EARLY AFTN. INSTABILITY AHEAD OF THE LINE WILL BE MARGINAL...THOUGH A NARROW TONGUE OF 50-55F DEW POINTS WILL LIKELY BE IN PLACE JUST AHEAD OF THE LINE. ANY POCKETS OF BOUNDARY LAYER HEATING WILL BOOST BUOYANCY AND THE FRONTAL CIRCULATION...CONTRIBUTING TO BRIEF STRONGER UPDRAFTS. MOREOVER...LARGELY UNIDIRECTIONAL WSWLY FLOW REGIME AOA 30-40 KTS JUST ABOVE THE SFC COULD CAUSE LOCAL OUTFLOW ACCELERATIONS/SMALL SCALE BOWS TO DEVELOP WITH ATTENDANT ISOLD DAMAGING WINDS...PRIMARILY LATER THIS MORNING. OTHERWISE...SMALL HAIL MAY OCCUR WITH THE STRONGER UPDRAFTS. ..RACY.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BTV...ALY...BGM...BUF... 42117709 43277633 44137580 45067388 44687313 43957298 43017311 42287329 41947381 41627555 WWWW From MCD at goshenarc.org Sat Apr 1 16:07:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 11:07:48 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011607 SWOMCD SPC MCD 011606 ARZ000-TXZ000-OKZ000-011800- MESOSCALE DISCUSSION 0388 NWS STORM PREDICTION CENTER NORMAN OK 1006 AM CST SAT APR 01 2006 AREAS AFFECTED...ERN OK...WRN AR...NE TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011606Z - 011800Z A WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A MORE ORGANIZED SEVERE THREAT. A STRONGER RETURN FLOW OF GULF MOISTURE THROUGH THE SOUTHERN/ EASTERN PLAINS IS BECOMING JUXTAPOSED WITH ZONE OF STRONGER LOW/MID LEVEL WARM ADVECTION IN WAKE OF LARGE NORTHEASTERN STATES UPPER TROUGH...AND AHEAD OF LARGE TROUGH PROGRESSING INTO THE INTERMOUNTAIN WEST. THIS APPEARS TO BE PROVIDING SUPPORT FOR RECENT CONVECTIVE DEVELOPMENT ACROSS NORTHEASTERN OKLAHOMA...WITH ADDITIONAL ACTIVITY POSSIBLE AS INHIBITION WEAKENS INTO EARLY AFTERNOON THROUGH A RATHER BROAD AREA OF EASTERN TEXAS/OKLAHOMA INTO THE LOWER MISSISSIPPI VALLEY. THOUGH...IN GENERAL...FLOW FIELDS ARE RELATIVELY WEAK...SHEAR SEEMS SUFFICIENT FOR AT LEAST BRIEF UPDRAFT ROTATION IN STRONGER CELLS DEVELOPING IN ENVIRONMENT WITH CAPE ON THE ORDER OF 1000 J/KG. ISOLATED MARGINALLY SEVERE HAIL APPEARS MOST LIKELY THREAT WITH INITIAL STORMS...AND THIS THREAT COULD INCREASE AS ACTIVITY BECOMES INCREASING SURFACE BASED THIS AFTERNOON. GIVEN PRESENCE OF DRY MID-LEVEL ENVIRONMENT...CONTINUED HEATING OF THE BOUNDARY LAYER WILL ALSO CONTRIBUTE TO AN INCREASING RISK OF ISOLATED DOWNBURSTS BY PEAK HEATING. MOST CONVECTION LIKELY WILL REMAIN RATHER UNORGANIZED. HOWEVER... FORCING ASSOCIATED WITH SUBTROPICAL IMPULSE PROGRESSING THROUGH BROADER SCALE RIDGE COULD AID THE EVOLUTION OF A LARGE CONVECTIVE CLUSTER IN CONFLUENT LOW-LEVEL FLOW REGIME...FROM PARTS OF EASTERN OKLAHOMA ACROSS CENTRAL/SOUTHERN ARKANSAS BY 21Z. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 35789620 36249569 36019416 35659271 35399165 34739115 33979121 33249281 33259393 33629499 33889552 34679610 34869614 WWWW From MCD at goshenarc.org Sat Apr 1 16:35:09 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 11:35:09 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011634 SWOMCD SPC MCD 011633 NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-NCZ000-011830- MESOSCALE DISCUSSION 0389 NWS STORM PREDICTION CENTER NORMAN OK 1033 AM CST SAT APR 01 2006 AREAS AFFECTED...SE VA THRU THE DELMARVA PEN INTO SRN NJ CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011633Z - 011830Z NEED FOR A WW IS NOT ANTICIPATED AT THE MOMENT DUE TO ANTICIPATED MARGINAL/LOCALIZED NATURE OF SEVERE THREAT...BUT TRENDS ARE BEING MONITORED. PRE-FRONTAL LOW-LEVEL THERMAL RIDGE AXIS EXTENDS EAST OF THE SOUTHERN APPALACHIANS THROUGH NORTHERN/MID ATLANTIC COASTAL AREAS. THIS FEATURE WILL BECOME THE FOCUS FOR STRONGEST DESTABILIZATION ...AND CONVECTIVE DEVELOPMENT...AS MID-LEVEL THERMAL TROUGH AXIS OVERSPREADS REGION THIS AFTERNOON. THIS SEEMS LIKELY TO COMMENCE BY 18Z...MOSTLY SOUTH/EAST OF THE WASHINGTON D.C. AREA...WITH ACTIVITY GRADUALLY INCREASING IN COVERAGE ACROSS SOUTHEAST VIRGINIA...THE DELMARVA PENINSULA...POSSIBLY THROUGH NEW JERSEY BY 21Z. IN GENERAL...MOISTURE LEVELS APPEAR MARGINAL FOR VIGOROUS UPDRAFTS...BUT STRONGER SURFACE HEATING ACROSS PARTS OF SOUTHEAST VIRGINIA AND THE SOUTHERN DELMARVA COULD COMPENSATE SOMEWHAT... CONTRIBUTING TO MIXED LAYER CAPE LOCALLY AS HIGH AS 1000 J/KG BY PEAK HEATING. IN MODERATE TO STRONGLY SHEARED AND COOL CYCLONIC FLOW REGION...THIS WILL CONTRIBUTE TO POTENTIAL FOR ISOLATED SEVERE STORMS...WITH LARGE HAIL/DAMAGING WIND GUSTS. OTHER STORMS FARTHER NORTH COULD ALSO APPROACH OR BRIEFLY EXCEED SEVERE CRITERIA. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...LWX...RAH... 36507587 36307670 36547813 36947830 37597767 38147706 38797655 39437597 39937521 40367449 40417419 40317376 WWWW From MCD at goshenarc.org Sat Apr 1 18:13:40 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 13:13:40 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 011812 SWOMCD SPC MCD 011812 KSZ000-OKZ000-TXZ000-COZ000-011945- MESOSCALE DISCUSSION 0390 NWS STORM PREDICTION CENTER NORMAN OK 1212 PM CST SAT APR 01 2006 AREAS AFFECTED...PARTS OF SE CO/WRN KS SOUTHWARD THRU FAR WRN OK AND MUCH OF THE TX PNHDL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 011812Z - 011945Z SEVERE THREAT IS EXPECTED TO INCREASE BY 03/21Z...WITH INCREASING TORNADIC POTENTIAL BY 02/00Z. A TORNADO WATCH MAY BECOME NECESSARY BY 20Z. UNCERTAINTIES CONCERNING CONVECTIVE DEVELOPMENT ARE STILL CONSIDERABLE. BUT...IT SEEMS MOST PROBABLE THAT FORCING ASSOCIATED WITH SHEARING IMPULSE COULD SUPPORT CONVECTIVE INITIATION IN BROKEN LINE ACROSS THE TEXAS/OKLAHOMA PANHANDLE REGION...AS IT LIFTS OUT OF BROADER SCALE WESTERN TROUGH INTO CENTRAL U.S.. RIDGE. DRY LINE IS EXPECTED TO SHARPEN NEAR THE ELKHART/AMARILLO/LUBBOCK AREAS BY PEAK HEATING...PROVIDING FOCUS FOR CONVECTIVE DEVELOPMENT...WHICH SHOULD QUICKLY BECOME SEVERE IN STRONGLY SHEARED...CONVECTIVELY UNSTABLE ENVIRONMENT. MIXED LAYER CAPE IS EXPECTED TO INCREASE IN EXCESS OF 2000 J/KG ALONG/EAST OF DRY LINE...CONTRIBUTING TO INTENSE UPDRAFTS. ALTHOUGH A LINE OF CONVECTION COULD EVOLVE SHORTLY AFTER INITIATION...SUPERCELLS ALSO APPEAR LIKELY WITHIN AND AHEAD OF LINE. CONVECTION WILL DEVELOP NORTHEASTWARD TOWARD THE DODGE CITY...GAGE AND CHILDRESS/ALTUS AREAS BETWEEN 21-00Z... ENCOUNTERING INCREASING MOIST BOUNDARY LAYER. AS THIS OCCURS...AND MID/UPPER JET STREAK BEGINS TO NOSE OUT OF THE SOUTHERN ROCKIES...ACCOMPANIED BY DEEPENING SURFACE LOW ACROSS EAST CENTRAL/SOUTHEAST COLORADO...HODOGRAPHS/THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASINGLY FAVORABLE FOR TORNADOES BY EARLY EVENING. ISOLATED LONG-LIVED SUPERCELLS ARE POSSIBLE...WITH ATTENDANT RISK FOR VERY LARGE HAIL AND POTENTIAL FOR STRONG TORNADOES. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...DDC...GLD...LUB...AMA...PUB... 35880221 36740221 38070159 38750044 38349942 37459977 36139957 34969937 34269984 33390101 33000228 33580244 34250235 35000200 WWWW From MCD at goshenarc.org Sat Apr 1 20:22:44 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 15:22:44 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012022 SWOMCD SPC MCD 012021 TXZ000-012145- MESOSCALE DISCUSSION 0391 NWS STORM PREDICTION CENTER NORMAN OK 0221 PM CST SAT APR 01 2006 AREAS AFFECTED...WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 012021Z - 012145Z WE ARE MONITORING THE DRYLINE SOUTH OF LBB FOR DEVELOPMENT. AN ADDITIONAL WW MAY BE REQUIRED NEXT HOUR OR SO. AIR MASS CONTINUES TO DESTABILIZE E OF DRYLINE WITH TEMPERATURES RISING INTO THE LOWER 80S. MODIFIED 18Z MIDLAND SOUNDING YIELDS STRONG INSTABILITY USING LOWER 60S DEWPOINT WITH LITTLE INHIBITION. ALTHOUGH CONVECTIVE INHIBITION IS STRONG FARTHER E AS SEEN ON OUN AND FWD SOUNDINGS...APPROACHING TROUGH WILL CONTINUE TO COOL TEMPERATURES WITHIN CAPPING LAYER AND REDUCE CIN. GIVEN A FEW MORE HOURS OF HEATING...AND INCREASING CONVERGENCE ALONG DRYLINE...AT LEAST ISOLATED DEVELOPMENT APPEARS LIKELY. EXISTING SHEAR PROFILES AT 20Z ALREADY FAVOR SUPERCELLS AND WILL ONLY INCREASE WITH TIME AS LOW LEVEL JET STRENGTHENS. THUS...VERY LARGE HAIL AND TORNADOES WILL BE POSSIBLE ESPECIALLY OVER NRN PARTS OF DISCUSSION AREA. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 33820150 33799906 32549891 31869885 31660123 32350131 33190139 WWWW From MCD at goshenarc.org Sat Apr 1 21:17:38 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 16:17:38 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012117 SWOMCD SPC MCD 012116 NEZ000-KSZ000-012245- MESOSCALE DISCUSSION 0392 NWS STORM PREDICTION CENTER NORMAN OK 0316 PM CST SAT APR 01 2006 AREAS AFFECTED...NW KS INTO SW NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 012116Z - 012245Z AN ADDITIONAL WW WILL LIKELY BE NEEDED WITHIN NEXT HOUR OR TWO. SURFACE LOW OVER EAST CENTRAL COLORADO IS SLOWLY DEEPENING...AND FORECAST TO CONTINUE TO DO SO INTO THE EARLY EVENING HOURS... PERHAPS SHIFTING TOWARD THE GOODLAND AREA BY 02-03Z. THIS WILL OCCUR AS INITIAL SHEARING IMPULSE LIFTS OUT OF THE SOUTHERN ROCKIES TOWARD CREST OF BROADER SCALE RIDGING OVER THE PLAINS/MISSISSIPPI VALLEY REGION. IN RESPONSE TO STRONGER SURFACE PRESSURE FALLS AND STRENGTHENING SOUTHEASTERLY FLOW TO THE EAST/NORTHEAST OF LOW...BOUNDARY LAYER IS IN PROCESS OF RAPIDLY DESTABILIZING ACROSS WESTERN KANSAS. SIMILAR DESTABILIZATION IS EXPECTED INTO AREAS SOUTH/EAST OF NORTH PLATTE NEB BY AROUND 00Z. THIS IS EXPECTED TO SUPPORT INCREASING POTENTIAL FOR STRONG/SEVERE THUNDERSTORM ACTIVITY. DEVELOPMENT IS ALREADY UNDERWAY ALONG DRY LINE FROM SOUTHWEST KANSAS INTO THE TEXAS PANHANDLE...AND NEW DEVELOPMENT APPEARS LIKELY THROUGH WARM SECTOR TO THE NORTH/EAST...BENEATH INCREASINGLY DIVERGENT UPPER FLOW. THIS IS EXPECTED BY 00Z...WITH FURTHER INCREASE EAST OF GOODLAND AND NORTH PLATTE INTO THE HILL CITY/GRAND ISLAND AREAS THROUGH 03Z. SHEAR PROFILES IN EXIT REGION OF APPROACHING MID-LEVEL JET STREAK WILL BE SUPPORTIVE OF SUPERCELLS IN ENVIRONMENT WITH CAPE RANGING FROM 1000 TO 2000 J/KG. VERY LARGE HAIL/DAMAGING WINDS AND ISOLATED TORNADOES ARE ALL LIKELY. ..KERR.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ICT...GID...LBF...DDC...GLD... 38460149 39060152 40330121 40970032 41179889 40969832 40199797 39309868 38699929 38490010 WWWW From MCD at goshenarc.org Sat Apr 1 22:10:27 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 17:10:27 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012209 SWOMCD SPC MCD 012208 OKZ000-KSZ000-TXZ000-020015- MESOSCALE DISCUSSION 0393 NWS STORM PREDICTION CENTER NORMAN OK 0408 PM CST SAT APR 01 2006 AREAS AFFECTED...SWRN KS / WRN OK / ERN TX PANHANDLE AND NW TX CONCERNING...TORNADO WATCH 121... VALID 012208Z - 020015Z THREAT FOR TORNADOES WILL INCREASE OVER THE NEXT FEW HOURS...WITH THE POTENTIAL FOR VERY LARGE DAMAGING HAIL AS WELL. STORMS CONTINUE TO DEVELOP E OF DRYLINE WHERE ENVIRONMENT HAS BECOME VERY UNSTABLE. SEVERAL CLUSTERS WERE NOTED ACROSS THE REGION...OVER SWRN KS...NEAR BGD AND SW OF CDS AT 22Z. MORE DEVELOPMENT IS LIKELY OVER FAR WRN OK WHERE TCU ARE RAPIDLY DEVELOPING. AREA PROFILERS INDICATE STRENGTHENING WIND FIELDS ALOFT WITH 50+ KT MID LEVEL FLOW ABOVE 3 KM ACROSS W TX. LOW LEVEL JET/850 FLOW IS ALSO INCREASING AND WILL PROVIDE AN INCREASINGLY FAVORABLE ENVIRONMENT FOR LONG LIVED SUPERCELLS. THUS...STORM STRUCTURE SHOULD BECOME MORE ORGANIZED WITH TIME...WITH THREAT OF TORNADOES INCREASING WITH LOW LEVEL SHEAR. ..JEWELL.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...DDC...LUB...AMA... 33779854 33780127 38190145 38199848 WWWW From MCD at goshenarc.org Sat Apr 1 23:38:12 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 18:38:12 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 012337 SWOMCD SPC MCD 012337 KSZ000-OKZ000-020100- MESOSCALE DISCUSSION 0394 NWS STORM PREDICTION CENTER NORMAN OK 0537 PM CST SAT APR 01 2006 AREAS AFFECTED...MUCH OF OK INTO CENTRAL KS CONCERNING...TORNADO WATCH 121...123... VALID 012337Z - 020100Z ...TORNADO WATCH WILL BE REQUIRED DOWNSTREAM ACROSS MUCH OF CENTRAL KS INTO SRN OK... MULTIPLE SUPERCELL CLUSTERS ARE EVOLVING ACROSS WRN KS...SWD INTO NWRN TX. THIS ACTIVITY WILL CONTINUE TO EVOLVE AS IT SPREADS DOWNSTREAM INTO CENTRAL PORTIONS OF KS AND OK OVER THE NEXT FEW HOURS. LATEST MODEL GUIDANCE STRONGLY SUGGESTS LLJ WILL INCREASE SIGNIFICANTLY OVER THE NEXT 3 HOURS ALONG I-35 CORRIDOR. THIS WILL AID LOW LEVEL SHEAR AND STORM INFLOW FOR MAINTAINING SUPERCELL STRUCTURES EAST OF CURRENT WATCHES. TORNADO WATCH WILL BE ISSUED FOR THIS REGION BY 01Z. ..DARROW.. 04/01/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...TOP...ICT...OUN...DDC... 34329854 38179837 38989733 38189608 34419658 WWWW From MCD at goshenarc.org Sun Apr 2 00:31:34 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 19:31:34 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020030 SWOMCD SPC MCD 020030 ARZ000-OKZ000-020200- MESOSCALE DISCUSSION 0395 NWS STORM PREDICTION CENTER NORMAN OK 0630 PM CST SAT APR 01 2006 AREAS AFFECTED...AR CONCERNING...SEVERE THUNDERSTORM WATCH 122... VALID 020030Z - 020200Z ...LARGE HAIL MAY STILL ACCOMPANY STRONGER STORMS... WARM ADVECTION ALONG RETREATING WARM FRONT WILL CONTINUE TO AID NWD CONVECTIVE DEVELOPMENT ACROSS CNTRL/NRN AR THIS EVENING. WITH LOSS OF DAYTIME HEATING...IT APPEARS INSTABILITY WILL GRADUALLY WANE LESSENING SEVERE POTENTIAL WITH THIS NWD PROPAGATION. GIVEN DYNAMIC PROCESSES ARE BECOMING MORE FOCUSED ACROSS CNTRL OK INTO KS...LARGE SCALE PROCESSES WILL NOT PROVE TOO SUPPORTIVE FOR SUSTAINING ORGANIZED SEVERE ACROSS THIS REGION AFTER DARK. NOT ADDITIONAL WATCHES ARE ANTICIPATED AT THIS TIME. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...TSA... 33729237 34549423 36209493 36029262 34299111 WWWW From MCD at goshenarc.org Sun Apr 2 01:39:31 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 20:39:31 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020138 SWOMCD SPC MCD 020138 NEZ000-KSZ000-020315- MESOSCALE DISCUSSION 0396 NWS STORM PREDICTION CENTER NORMAN OK 0738 PM CST SAT APR 01 2006 AREAS AFFECTED...SERN NEB...NERN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020138Z - 020315Z ...SEVERE THREAT IS INCREASING ACROSS SERN NEB AND NERN KS. SEVERE THUNDERSTORM WATCH WILL BE ISSUED SOON... SQUALL LINE WITH EMBEDDED SUPERCELL STRUCTURES IS BECOMING A BIT MORE ORGANIZED AS IT LIFTS NEWD ACROSS CNTRL KS THIS EVENING. IT APPEARS THIS ACTIVITY WILL PROGRESS EAST AND NORTH OF CURRENT TORNADO WATCHES INTO A SLOWLY DESTABILIZING AIRMASS CAPABLE OF MAINTAINING DAMAGING WINDS AND LARGE HAIL THREAT. STRENGTH OF UPPER SHORTWAVE/ENHANCED LIFT SUGGEST SQUALL LINE WILL NOT DECREASE SIGNIFICANTLY IN INTENSITY OVER THE NEXT FEW HOURS. SEVERE THUNDERSTORM WATCH WILL LIKELY BE ISSUED SOON. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...TOP...GID... 38689709 40089786 40439930 41319826 40489613 38379551 WWWW From MCD at goshenarc.org Sun Apr 2 01:53:50 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 20:53:50 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020153 SWOMCD SPC MCD 020153 TXZ000-020330- MESOSCALE DISCUSSION 0397 NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CST SAT APR 01 2006 AREAS AFFECTED...SWRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020153Z - 020330Z ...SEVERE THUNDERSTORM WATCH MAY BE REQUIRED FOR PORTIONS OF SWRN/CNTRL TX... CONVECTION HAS RAPIDLY INCREASED OVER SWRN TX ALONG DRY LINE FROM ERN PECOS COUNTY INTO REAGAN COUNTY. DRT SOUNDING AT 00Z WAS NOT TERRIBLY CAPPED WITH WEAK MID LEVEL CAA NOTED AROUND 700MB. IT APPEARS SRN END OF PLAINS SHORTWAVE TROUGH WILL EJECT ACROSS PORTIONS OF CNTRL TX AIDING THIS CONVECTION IN THE SHORT TERM. ALTHOUGH FWD SOUNDING EXHIBITED QUITE A BIT MORE INHIBITION...SHEAR PROFILES SEEM FAVORABLE FOR SUSTAINING SQUALL LINE STRUCTURE AS IT SPREADS ACROSS THE EDWARDS PLATEAU OVER THE NEXT SEVERAL HOURS. SEVERE THUNDERSTORM WATCH MAY BE REQUIRED IF TRENDS CONTINUE. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SJT...MAF... 30700178 31520103 32200013 31669901 30630096 WWWW From MCD at goshenarc.org Sun Apr 2 02:18:32 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 01 Apr 2006 21:18:32 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020217 SWOMCD SPC MCD 020217 OKZ000-TXZ000-020345- MESOSCALE DISCUSSION 0398 NWS STORM PREDICTION CENTER NORMAN OK 0817 PM CST SAT APR 01 2006 AREAS AFFECTED...CENTRAL OK CONCERNING...TORNADO WATCH 124... VALID 020217Z - 020345Z ...TORNADO THREAT APPEARS TO BE DECREASING ACROSS OK... SQUALL LINE HAS ORGANIZED ACROSS WRN OK AND IS SURGING ENEWD AT ROUGHLY 35KT. SUPERCELL STRUCTURES HAVE GRADUALLY DECREASED IN INTENSITY ALONG THIS LINE AND HAVE BECOME ILL DEFINED AS CELL MERGERS HAVE EVOLVED INTO BOW-LIKE STRUCTURES. IT APPEARS THE GREATEST RISK OF SEVERE OVER THE NEXT FEW HOURS WILL BE LARGE HAIL...ALONG WITH THE THREAT OF STRONG WINDS...ESPECIALLY AHEAD OF BOW-TYPE FEATURES. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...OUN... 36699636 34939684 34059792 34239894 34989825 36719788 WWWW From MCD at goshenarc.org Sun Apr 2 06:44:59 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 01:44:59 -0500 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 020644 SWOMCD SPC MCD 020644 MOZ000-ARZ000-OKZ000-KSZ000-020845- MESOSCALE DISCUSSION 0399 NWS STORM PREDICTION CENTER NORMAN OK 1244 AM CST SUN APR 02 2006 AREAS AFFECTED...EXTREME ERN KS...WRN/CNTRL MO...ECNTRL OK AND NWRN/NCNTRL AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 020644Z - 020845Z LINEAR MCS CONTINUES TO MOVE FROM ERN OK AND ERN KS TOWARD WRN MO AND NWRN AR EARLY THIS MORNING. BOWING PORTION OF THE LINE WILL BE MOVING ACROSS WS 127 AT 45 KTS INTO SWRN MO AND NWRN AR WITH GUSTY AND POTENTIALLY DAMAGING WIND GUSTS THROUGH 8-9Z. HOWEVER... DIAGNOSTIC DATA SUGGESTS THAT STORMS WILL BECOME MORE ELEVATED AS THEY MOVE EWD INTO THE OZARKS. THUS...IT APPEARS THE SEVERE THREATS WILL DIMINISH WITH TIME AND A NEW WW IS NOT ANTICIPATED DOWNSTREAM INTO CNTRL MO OR NCNTRL AR. ..RACY.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...LZK...SGF...EAX...TSA...TOP...OUN... 39689532 39759370 39229290 38189235 37429218 36499216 35969243 35219362 34909623 36029494 37139460 38619525 WWWW From MCD at goshenarc.org Sun Apr 2 14:42:18 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 10:42:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021441 SWOMCD SPC MCD 021441 MOZ000-IAZ000-KSZ000-NEZ000-021645- MESOSCALE DISCUSSION 0400 NWS STORM PREDICTION CENTER NORMAN OK 0941 AM CDT SUN APR 02 2006 AREAS AFFECTED...NE KS...NW MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021441Z - 021645Z TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A WW...WHICH COULD BECOME NECESSARY BY 18-20Z...IF NOT BEFORE. COLD CORE OF VIGOROUS MID-LEVEL TROUGH IS BEGINNING TO TAKE ON A NEGATIVE TILT ACROSS THE CENTRAL PLAINS. ASSOCIATED FORCING FOR UPWARD VERTICAL MOTION AND DESTABILIZATION IS SUPPORTING ONGOING INCREASING CONVECTIVE DEVELOPMENT...JUST TO THE WEST/SOUTH WEST OF SLOWLY DEEPENING SURFACE LOW AND TRAILING DRY LINE. SURFACE LOW IS CURRENTLY CENTERED NORTH NORTHWEST OF MANHATTAN KS...AND WILL CONTINUE TO GRADUALLY MIGRATE ALONG EASTWARD EXTENDING WARM FRONT ...TOWARD THE ST. JOSEPH MO AREA THROUGH 18Z. INSOLATION IN WARM SECTOR ACROSS NORTHEAST KANSAS INTO NORTHWEST/ WEST CENTRAL MISSOURI WILL BEGIN TO DESTABILIZE BOUNDARY LAYER... BUT ENVIRONMENT ON NOSE OF ELEVATED MIXED LAYER WRAPPING INTO CYCLONE IS ALREADY POTENTIALLY MODERATELY UNSTABLE. AS STRONGER FORCING BEGINS TO OVERSPREAD WARM SECTOR THROUGH MID DAY... INCREASING/INTENSIFYING TRENDS TO CONVECTIVE DEVELOPMENT WILL CONTINUE. LARGE HAIL WILL INITIALLY BE PRIMARY THREAT ACROSS NORTH CENTRAL INTO NORTHEAST KANSAS. BUT...AS ACTIVITY PROGRESSES INTO THE ST. JOSEPH/KANSAS CITY MO AREAS...POTENTIAL FOR DAMAGING WINDS WILL INCREASE AS ACTIVITY BECOMES INCREASINGLY ORGANIZED IN STRONGLY SHEARED CONVECTIVE UNSTABLE ENVIRONMENT. SQUALL LINE MAY BEGIN TO EVOLVE EASTWARD INTO NORTHWESTERN MISSOURI THROUGH THE 18-21Z TIME FRAME. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...DMX...EAX...OAX...TOP...ICT...GID... 40489761 40769613 40669474 40529369 40039297 39399272 38769310 38239372 37749431 37859525 38469562 39079690 39389767 WWWW From MCD at goshenarc.org Sun Apr 2 15:43:11 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 11:43:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021542 SWOMCD SPC MCD 021542 TNZ000-KYZ000-ILZ000-MOZ000-MSZ000-ARZ000-021715- MESOSCALE DISCUSSION 0401 NWS STORM PREDICTION CENTER NORMAN OK 1042 AM CDT SUN APR 02 2006 AREAS AFFECTED...ERN AR...SE MO...WRN KY...WRN TN...NW MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021542Z - 021715Z WW IS NOT ANTICIPATED IN SHORT TERM...BUT TRENDS ARE BEING MONITORED. IN WAKE OF INITIAL WEAKENING SHORT WAVE TROUGH...NOW LIFTING THROUGH THE UPPER MISSISSIPPI VALLEY...AND A MORE SUBTLE SUBTROPICAL STREAM IMPULSE...LIFTING ACROSS EASTERN ARKANSAS TOWARD THE TENNESSEE VALLEY...LOW-LEVEL FLOW HAS VEERED TO WESTERLY ACROSS MISSOURI ARKANSAS. THIS HAS CONTRIBUTED TO INCREASING WARM ADVECTION ON EASTERN FRINGE OF LOW-LEVEL THERMAL RIDGE WRAPPING INTO DEEP SURFACE LOW CENTERED OVER NORTHEAST KANSAS/SOUTHEAST NEBRASKA. AS FORCING SPREADS EASTWARD OF THE OZARKS TOWARD THE MISSOURI RIVER...SCATTERED STORMS CONTINUE TO DEVELOP. WARM SECTOR BOUNDARY LAYER TO THE EAST OF ONGOING ACTIVITY IS WARMING WITH INSOLATION...BUT NOT LIKELY TO BECOME DEEPLY MIXED UNTIL MID/LATE AFTERNOON. THUS...THROUGH THE 18-19Z TIME FRAME SCATTERED CONVECTION SEEMS LIKELY TO REMAIN ROOTED ABOVE INVERSION LAYER. ANY SEVERE THREAT SEEMS LIKELY TO BE LIMITED TO ISOLATED MARGINALLY SEVERE HAIL ASSOCIATED WITH MOST UNSTABLE CAPE TO 1000 J/KG IN FAVORABLY SHEARED ENVIRONMENT. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...MEG...JAN...LSX...LZK... 33809150 33799236 34599269 35529180 36399111 36909100 37499065 37328955 36908839 36348811 35058948 33919107 WWWW From MCD at goshenarc.org Sun Apr 2 16:04:15 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 12:04:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021603 SWOMCD SPC MCD 021603 TXZ000-021800- MESOSCALE DISCUSSION 0402 NWS STORM PREDICTION CENTER NORMAN OK 1103 AM CDT SUN APR 02 2006 AREAS AFFECTED...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021603Z - 021800Z TRENDS ARE BEING MONITORED...WW COULD BECOME NECESSARY SHORTLY. MID-LEVEL HEIGHT FALLS HAVE WEAKENED INHIBITION SUFFICIENTLY FOR INITIAL OF VIGOROUS CONVECTIVE DEVELOPMENT TO THE SOUTH OF WACO. VEERING LOW/MID TROPOSPHERIC FLOW AND SUBSEQUENT COOLING APPEAR LIKELY TO CONTRIBUTE TO FURTHER WEAKENING OF CAP THROUGH EARLY AFTERNOON...IN CONFLUENT LOW-LEVEL FLOW REGIME NORTH/WEST OF WACO INTO THE TYLER/LONGVIEW AREAS. THIS MAY SUPPORT INCREASINGLY WIDESPREAD CONVECTIVE DEVELOPMENT IN ENVIRONMENT WITH MIXED LAYER CAPE OF 2000 TO 3000 J/KG. GIVEN FAVORABLE SHEAR...CONVECTIVE INSTABILITY ASSOCIATED WITH DRY MID-LEVELS WILL BE SUPPORT OF SEVERE STORMS WITH DAMAGING WINDS...IN ADDITION TO LARGE HAIL. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX...SJT... 31009901 31769863 32319735 32889605 33369523 33029433 32029441 31239522 30929703 30429915 WWWW From MCD at goshenarc.org Sun Apr 2 16:35:28 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 12:35:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021634 SWOMCD SPC MCD 021634 MOZ000-021830- MESOSCALE DISCUSSION 0403 NWS STORM PREDICTION CENTER NORMAN OK 1134 AM CDT SUN APR 02 2006 AREAS AFFECTED...CNTRL THROUGH SW/S CNTRL MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021634Z - 021830Z A TORNADO WW WILL PROBABLY BE NEEDED BY AROUND 18Z...OR SHORTLY THEREAFTER. MOISTENING/HEATING OF BOUNDARY LAYER IS CONTRIBUTING TO INCREASING POTENTIAL INSTABILITY IN WARM SECTOR...EAST OF DRY LINE/COLD FRONT TRAILING FROM SLOWLY DEEPENING SURFACE LOW WHICH IS NOW WEST/NORTHWEST OF ST. JOSEPH MO. LEADING EDGE OF STRONGER MID-LEVEL COOLING ALREADY APPEARS TO BE OVERSPREADING DEVELOPING INSTABILITY AXIS...AND INHIBITION IS WEAKENING. THIS MAY BECOME SUPPORTIVE OF NEW BOUNDARY LAYER-BASED CONVECTIVE INITIATION AS EARLY AS 18-20Z SOUTHEAST OF THE KANSAS CITY INTO THE SPRINGFIELD AREA. BROKEN SQUALL LINE SEEMS LIKELY TO QUICKLY EVOLVE...IN ENVIRONMENT WITH MIXED LAYER INCREASING IN EXCESS OF 2000 J/KG. 70 KT MID-LEVEL JET STREAK NOSING INTO THE OZARK PLATEAU WILL CONTRIBUTE TO DEEP LAYER SHEAR SUFFICIENT FOR SUPERCELLS. THOUGH LOW-LEVEL HODOGRAPHS MAY NOT POSSESS STRONG CLOCKWISE CURVATURE...SHEAR BENEATH 30 TO 40 TO WESTERLY 850 FLOW WILL STILL BE SUPPORTIVE OF TORNADIC ACTIVITY...PARTICULARLY IN STRONGER/MORE ISOLATED CELLS WITHIN LINE. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX... 38049433 38719402 39699329 39509222 39159166 38219149 37659170 36779206 36549322 36599383 37069429 WWWW From MCD at goshenarc.org Sun Apr 2 18:15:16 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 14:15:16 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021814 SWOMCD SPC MCD 021814 TNZ000-KYZ000-GAZ000-ALZ000-MSZ000-021945- MESOSCALE DISCUSSION 0404 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT SUN APR 02 2006 AREAS AFFECTED......PARTS OF NE MS/NRN AL AND MIDDLE/EASTERN TN INTO PARTS OF S CNTRL/SE KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021814Z - 021945Z TRENDS CONTINUE TO BE MONITORED FOR INCREASING SEVERE THREAT AND THE POSSIBILITY OF A WW. EMBEDDED WITHIN MODERATELY STRONG MEAN SOUTHWESTERLY FLOW REGIME... SMALL CONVECTIVE CLUSTER APPEARS LIKELY TO BEGIN TO SHIFT AWAY FROM SUPPORTING STRONGER LOW-LEVEL WARM ADVECTION REGIME OVER THE LOWER MISSISSIPPI VALLEY. HOWEVER...MOIST BOUNDARY LAYER AHEAD OF ACTIVITY INTO RETREATING WARM FRONT ALONG THE WESTERN SLOPES OF THE APPALACHIANS CONTINUES TO BECOME MORE DEEPLY MIXED AND SUSCEPTIBLE TO SURFACE-BASED CONVECTIVE DEVELOPMENT. AS CLUSTER SPREADS INTO EXTREME NORTHERN ALABAMA/MIDDLE TENNESSEE BY 20-21Z...THIS MAY OCCUR ALONG LEADING EDGE OF STRENGTHENING SURFACE COLD POOL. GIVEN LIKELY CONTINUED EAST NORTHEAST MOTION OF 40+ KT...TENDENCY FOR STRONG SURFACE GUSTS APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS MAY INCREASE LATE THIS AFTERNOON. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...FFC...LMK...OHX...HUN...PAH...MEG... 35838823 36588764 37268540 36998431 36468407 35668430 35348481 34918552 34638617 34448722 34418761 35008835 WWWW From MCD at goshenarc.org Sun Apr 2 19:16:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 15:16:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 021916 SWOMCD SPC MCD 021915 ARZ000-MOZ000-022045- MESOSCALE DISCUSSION 0405 NWS STORM PREDICTION CENTER NORMAN OK 0215 PM CDT SUN APR 02 2006 AREAS AFFECTED...AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 021915Z - 022045Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT. A NEW WW MAY BE NEEDED BY AROUND 21Z OR SHORTLY THEREAFTER. WARM SECTOR BOUNDARY LAYER WITH LOWER/MID 60S DEW POINTS IS NOW WARMING INTO THE LOWER 80S ACROSS MUCH OF WESTERN AND CENTRAL ARKANSAS. THIS HAS CONTRIBUTED TO MODERATE INSTABILITY...WITH CAPE INCREASING TO AROUND 2000 J/KG. INFLUENCE OF SUBSIDENCE/DRYING IN BASE OF APPROACHING SHORT WAVE TROUGH IS STILL UNCERTAIN AT THE PRESENT TIME...BUT IT APPEARS CONVECTIVE INITIATION IS NOT AS IMMINENT AS AREAS FARTHER TO THE NORTH. HOWEVER...WITH TIME...MODELS SUGGEST EROSION OF MID-LEVEL INHIBITION BY LATE AFTERNOON WITH LOWER/MID TROPOSPHERIC COOLING AND ADDITIONAL SURFACE HEATING. THIS MAY BECOME SUPPORTIVE OF CONVECTIVE INITIATION AS EARLY AS 21-22Z. STRONG SHEAR NEAR 70 KT MID-LEVEL JET STREAK NOSING INTO THE OZARK PLATEAU WILL CONTRIBUTE TO RAPID SUPERCELL DEVELOPMENT. POTENTIAL FOR VERY LARGE HAIL AND DAMAGING WIND GUSTS WILL EXIST IN STRONGER CELLS. ISOLATED TORNADOES ARE ALSO POSSIBLE. TORNADO POTENTIAL COULD INCREASE LATE THIS AFTERNOON AS ACTIVITY SPREADS FROM CENTRAL INTO EASTERN ARKANSAS...WHERE SURFACE FLOW MAY MAINTAIN A MORE SOUTHERLY COMPONENT AND LARGER LOW-LEVEL HODOGRAPHS. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...JAN...LZK...SGF...SHV... 35569341 36029307 36339245 36519155 36309097 35839067 35009070 34529099 33819118 33219219 33099276 33209379 33769402 34459416 34979381 WWWW From MCD at goshenarc.org Sun Apr 2 20:17:02 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 16:17:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022016 SWOMCD SPC MCD 022016 ILZ000-MOZ000-IAZ000-022145- MESOSCALE DISCUSSION 0406 NWS STORM PREDICTION CENTER NORMAN OK 0316 PM CDT SUN APR 02 2006 AREAS AFFECTED...CNTRL/ERN MO CONCERNING...TORNADO WATCH 130... VALID 022016Z - 022145Z CONTINUE WW. POTENTIAL FOR TORNADOES MAY INCREASE NEXT FEW HOURS ACROSS PARTS OF NORTHEAST/EAST CENTRAL MISSOURI. NEW WW MAY BE NEEDED NORTHEAST OF WW 130 BEFORE 21Z. RAPID CONVECTIVE DEVELOPMENT IS ONGOING ALONG PRE-FRONTAL INSTABILITY AXIS...TRAILING FROM DEEP SOUTHWEST IOWA SURFACE CYCLONE...SOUTHWARD THROUGH THE OZARKS. BROKEN SQUALL LINE WITH EMBEDDED SUPERCELLS WILL CONTINUE TO EVOLVE LATE THIS AFTERNOON... SPREADING EASTWARD AHEAD OF STRONGER MID-LEVEL FORCING THROUGH THE MIDDLE MISSISSIPPI VALLEY. DESPITE LACK OF MORE PRONOUNCED VEERING OF LOW-LEVEL WIND FIELDS IN WARM SECTOR...SHEAR APPEARS STRONG ENOUGH FOR RISK OF TORNADOES IN SUPERCELLS...IN ADDITION TO LARGE HAIL/DAMAGING WIND THREAT ALONG DEVELOPING LINE. BETTER RISK FOR TORNADOES MAY DEVELOP IN THE 21-00Z TIME FRAME...AS SUPERCELLS WITHIN LINE BEGIN TO CROSS OLD WARM FRONTAL ZONE EXTENDING ACROSS THE ST. LOUIS INTO THE QUINCY/OTTUMWA AREAS. WARM FRONT IS BEGINNING TO LIFT NORTH OF THIS REGION...BUT SURFACE WINDS MAY BE SLOWER TO VEER TO A WESTERLY COMPONENT...CONTRIBUTING TO STRONGER CLOCKWISE CURVATURE IN LOW LEVEL HODOGRAPHS. ..KERR.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...LOT...ILX...LSX...DVN...SGF...DMX...EAX... 41039285 41739264 42019165 42089067 41588928 40538889 39498889 38568920 37548986 36739113 36739330 38099278 39829255 WWWW From MCD at goshenarc.org Sun Apr 2 22:03:38 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 18:03:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022202 SWOMCD SPC MCD 022202 TXZ000-022330- MESOSCALE DISCUSSION 0407 NWS STORM PREDICTION CENTER NORMAN OK 0502 PM CDT SUN APR 02 2006 AREAS AFFECTED...NE TX CONCERNING...SEVERE THUNDERSTORM WATCH 129... VALID 022202Z - 022330Z AN ISOLATED LARGE HAIL AND WIND DAMAGE THREAT MAY INCREASE AS STORMS INITIATE AND EXPAND IN COVERAGE EARLY THIS EVENING. A WW MAY BECOME NECESSARY ACROSS THE REGION WITHIN THE NEXT FEW HOURS. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT IN PLACE EXTENDING SWWD FROM SE OK ACROSS THE DALLAS/FORT WORTH AREA. VISIBLE SATELLITE IMAGERY SHOWS TOWERING CUMULUS EVIDENT ALONG AND AHEAD OF THE BOUNDARY. AS A SHORTWAVE TROUGH APPROACHES THE AREA THIS EVENING...SCATTERED STORM INITIATION SHOULD TAKE PLACE DUE TO STRONG CONVERGENCE ALONG THE FRONT AND INCREASING LARGE-SCALE ASCENT. FORECAST SOUNDINGS THROUGH EARLY THIS EVENING SHOW 40 TO 45 KT OF VERTICAL SHEAR WITH LAPSE RATES AROUND 7.0 C/KM. THIS SHOULD BE SUFFICIENT FOR LARGE HAIL AND ISOLATED WIND DAMAGE CONSIDERING MODERATE INSTABILITY EXISTS ACROSS MOST OF NE TX. IF STORM COVERAGE CONTINUES TO SLOWLY INCREASE EARLY THIS EVENING AS MANY OF THE SHORT-TERM MODELS SUGGEST...A NEW WW MAY BECOME NECESSARY ACROSS THE REGION EARLY THIS EVENING. ..BROYLES.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD... 31629426 30959625 31209721 31979706 32889473 32349404 WWWW From MCD at goshenarc.org Sun Apr 2 23:52:32 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 19:52:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022351 SWOMCD SPC MCD 022351 INZ000-ILZ000-030045- MESOSCALE DISCUSSION 0408 NWS STORM PREDICTION CENTER NORMAN OK 0651 PM CDT SUN APR 02 2006 AREAS AFFECTED...ERN IL CONCERNING...TORNADO WATCH 133...137... VALID 022351Z - 030045Z ...MULTIPLE TORNADIC SUPERCELLS WILL RACE NEWD ACROSS ECNTRL IL... MULTIPLE TORNADIC SUPERCELLS ARE EMBEDDED WITHIN AN ELONGATED LINE OF SEVERE THUNDERSTORMS STRETCHING FROM HENRY COUNTY IL...SEWD INTO WAYNE COUNTY IL. A NARROW WEDGE OF UNSTABLE AIR SUPPORTIVE OF MAINTAINING THIS TORNADIC ACTIVITY HAS SPREAD INTO ECNTRL IL/SWRN IND. GIVEN STORM MOTION IS QUITE FAST...APPROACHING 50 KT...THERE IS SOME QUESTION AS TO THE DEGREE OF BOUNDARY LAYER DESTABILIZATION POSSIBLE DOWNSTREAM OVER CNTRL IND. EVEN SO...TORNADIC STRUCTURES AT SOME POINT WILL LIKELY EVOLVE INTO DAMAGING BOW-TYPE FEATURES THAT WILL RACE NEWD ACROSS THE REMAINDER OF WW137 WITH ACTIVITY REACHING WRN OH BY LATE EVENING. ..DARROW.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...LOT...ILX...LSX... 37958833 39158899 40528981 41008872 40358664 38768629 WWWW From MCD at goshenarc.org Sun Apr 2 23:59:41 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 19:59:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 022359 SWOMCD SPC MCD 022358 KYZ000-TNZ000-ALZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-030130- MESOSCALE DISCUSSION 0409 NWS STORM PREDICTION CENTER NORMAN OK 0658 PM CDT SUN APR 02 2006 AREAS AFFECTED...SRN IL...FAR NE AR...WRN TN AND WRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 134... VALID 022358Z - 030130Z A LINE OF SUPERCELLS ONGOING ACROSS SE MO AND NE AR WILL CONTINUE TO HAVE A THREAT OF TORNADOES...LARGE HAIL AND WIND DAMAGE OVER THE NEXT FEW HOURS. A TORNADO WATCH WILL LIKELY BECOME NECESSARY EAST OF THE CURRENT TORNADO WATCHES. LATEST SFC ANALYSIS SHOWS A LOW-LEVEL MOIST AXIS WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F EXTENDING NWD ACROSS WRN TN AND WRN KY. THIS IS IN THE VICINITY OF A 40 KT LOW-LEVEL JET WHICH WILL CONTINUE TO INCREASE THIS EVENING. THIS COMBINED WITH STRONG LIFT AND VERTICAL SHEAR ASSOCIATED WITH THE NOSE OF A MID-LEVEL JET WILL CONTINUE TO MAKE THE ENVIRONMENT VERY FAVORABLE FOR SUPERCELLS AND TORNADOES. AS THE SUPERCELLS MOVE INTO THE LOW-LEVEL JET...LONG TRACK SIGNIFICANT TORNADOES WILL REMAIN POSSIBLE OVER THE NEXT HOUR. THE SEVERE THREAT SHOULD CONTINUE EWD INTO CNTRL TN AND CNTRL KY AS THE SUPERCELLS TRACK EWD. LARGE HAIL...WIND DAMAGE AND TORNADOES WILL CONTINUE TO BE POSSIBLE THROUGH LATE THIS EVENING. ..BROYLES.. 04/02/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JKL...LMK...OHX...HUN...PAH...MEG... 34928659 35029019 35319072 36359013 37808890 37868570 36978497 35858896 35968989 36289005 36438974 36168848 35848859 WWWW From MCD at goshenarc.org Mon Apr 3 00:08:48 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 20:08:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030007 SWOMCD SPC MCD 030006 KYZ000-TNZ000-ALZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-030130- MESOSCALE DISCUSSION 0409 NWS STORM PREDICTION CENTER NORMAN OK 0706 PM CDT SUN APR 02 2006 AREAS AFFECTED...SRN IL...FAR NE AR...WRN TN AND WRN KY CONCERNING...SEVERE THUNDERSTORM WATCH 134... VALID 030006Z - 030130Z A LINE OF SUPERCELLS ONGOING ACROSS SE MO AND NE AR WILL CONTINUE TO HAVE A THREAT OF TORNADOES...LARGE HAIL AND WIND DAMAGE OVER THE NEXT FEW HOURS. A TORNADO WATCH WILL LIKELY BECOME NECESSARY EAST OF THE CURRENT TORNADO WATCHES. LATEST SFC ANALYSIS SHOWS A LOW-LEVEL MOIST AXIS WITH SFC DEWPOINTS IN THE LOWER TO MID 60S F EXTENDING NWD ACROSS WRN TN AND WRN KY. THIS IS IN THE VICINITY OF A 40 KT LOW-LEVEL JET WHICH WILL CONTINUE TO INCREASE THIS EVENING. THIS COMBINED WITH STRONG LIFT AND VERTICAL SHEAR ASSOCIATED WITH THE NOSE OF A MID-LEVEL JET WILL CONTINUE TO MAKE THE ENVIRONMENT VERY FAVORABLE FOR SUPERCELLS AND TORNADOES. AS THE SUPERCELLS MOVE INTO THE LOW-LEVEL JET...LONG TRACK SIGNIFICANT TORNADOES WILL REMAIN POSSIBLE OVER THE NEXT HOUR. THE SEVERE THREAT SHOULD CONTINUE EWD INTO CNTRL TN AND CNTRL KY AS THE SUPERCELLS TRACK EWD. LARGE HAIL...WIND DAMAGE AND TORNADOES WILL CONTINUE TO BE POSSIBLE THROUGH LATE THIS EVENING. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JKL...LMK...OHX...HUN...PAH...MEG... 34928659 35029019 35319072 36359013 37808890 37868570 36978497 WWWW From MCD at goshenarc.org Mon Apr 3 02:12:02 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 22:12:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030211 SWOMCD SPC MCD 030210 KYZ000-TNZ000-030415- MESOSCALE DISCUSSION 0410 NWS STORM PREDICTION CENTER NORMAN OK 0910 PM CDT SUN APR 02 2006 AREAS AFFECTED...WRN KY...MIDDLE/WRN TN CONCERNING...TORNADO WATCH 134...137...138... VALID 030210Z - 030415Z ...MULTIPLE DISCRETE TORNADIC SUPERCELLS HAVE EVOLVED ACROSS THE REGION... 00Z SOUNDING FROM LZK SUGGESTS HIGH QUALITY LAPSE RATE/INSTABILITY ENVIRONMENT IS SPREADING DOWNSTREAM ACROSS THE TN VALLEY WHERE MULTIPLE DISCRETE TORNADIC SUPERCELLS PERSIST. SEVERAL OF THESE STORMS ARE LONG-LIVED AND HAVE YET TO EXHIBIT ANY SIGNIFICANT WEAKENING. OVER THE LAST FEW HOURS...DIAGNOSTIC TRENDS ARE SHOWING RAPID RECOVERY INTO MIDDLE TN WHERE SIG TOR VALUES ARE NOW APPROACHING 8. TORNADIC THREAT REMAINS HIGH ACROSS THIS REGION FOR THE NEXT FEW HOURS...WITH THE POTENTIAL FOR STRONG TORNADOES. ..DARROW.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...PAH...MEG... 36118910 37458664 36738576 35728657 35048830 35088961 WWWW From MCD at goshenarc.org Mon Apr 3 02:28:06 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 22:28:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030227 SWOMCD SPC MCD 030227 OHZ000-KYZ000-INZ000-030400- MESOSCALE DISCUSSION 0411 NWS STORM PREDICTION CENTER NORMAN OK 0927 PM CDT SUN APR 02 2006 AREAS AFFECTED...ERN IN / CENTRAL AND NRN KY / OH / WRN WV CONCERNING...CONVECTIVE TRENDS VALID 030227Z - 030400Z INTENSE BOW ECHO CONTINUES TO MOVE EWD AT OVER 55 KTS ACROSS ERN INDIANA INTO NRN KY. RADAR PRESENTATION CONTINUES TO SHOW REAR INFLOW JET REFLECTION WITH LOW REFLECTIVITY HOLE JUST BEHIND MAIN BOW...SUGGESTING INTENSE AND WIDESPREAD WIND DAMAGE IS LIKELY. SWLY LOW LEVEL JET WILL CONTINUE TO ADVECT UNSTABLE AIR NEWD INTO OH AND WRN WV. EXTRAPOLATION SHOWS BOW INTO CENTRAL OH BY 4Z. ADDITIONALLY...THREAT FOR TORNADOES CONTINUES GIVEN VERY STRONG EXTREME SHEAR IN PLACE...WITH EITHER EMBEDDED ROTATION SIGNATURES WITHIN LINE OR WITH WARM ADVECTION CELLS AHEAD OF LINE. GREATEST TORNADO THREAT APPEARS TO BE OVER KY IN CLOSER PROXIMITY TO GREATER INSTABILITY. ..JEWELL.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...LMK...IWX...IND... 39178558 40748636 41418590 41588362 41288267 39728204 37768291 37558607 WWWW From MCD at goshenarc.org Mon Apr 3 03:45:34 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 02 Apr 2006 23:45:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030344 SWOMCD SPC MCD 030344 WVZ000-OHZ000-KYZ000-030415- MESOSCALE DISCUSSION 0412 NWS STORM PREDICTION CENTER NORMAN OK 1044 PM CDT SUN APR 02 2006 AREAS AFFECTED...SERN OH / WRN WV / ERN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030344Z - 030415Z A SEVERE THUNDERSTORM WATCH WILL BE ISSUED SHORTLY FOR PORTIONS OF OH...KY...AND WV. LINE OF THUNDERSTORMS CONTINUES TO MOVE EWD ACROSS THE REGION. WIND SPEEDS OVER 70 MPH WERE RECENTLY MEASURED OVER NRN KY. DESPITE RELATIVELY WEAK INSTABILITY AND VILS...FORCING REMAIN STRONG AS REFLECTED IN SURFACE PRESSURE RISE/FALL COUPLET. ..JEWELL.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...PBZ...RLX...JKL...ILN... 37518348 39908350 40048060 37818076 WWWW From MCD at goshenarc.org Mon Apr 3 05:40:52 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 01:40:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030539 SWOMCD SPC MCD 030539 ALZ000-030715- MESOSCALE DISCUSSION 0413 NWS STORM PREDICTION CENTER NORMAN OK 1239 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030539Z - 030715Z SEVERE TSTM RISK WILL INCREASE ACROSS NRN AL AFTER 07Z. A WW WILL LIKELY BE REQUIRED. A BAND OF TSTMS CONTINUES TO MOVE ACROSS SRN PORTIONS OF WRN/MIDDLE TN AND EXTREME NRN MS EARLY THIS MORNING. EMBEDDED WITHIN THE LINE WERE SEVERAL SUPERCELLS WITH LOW-LEVEL CIRCULATIONS. THE PORTION OF THE LINE ACROSS NRN MS IS EXPECTED TO APPROACH THE NWRN TIP OF AL BY 07Z. FORECAST RUC SOUNDINGS SUGGEST THE AIR MASS ACROSS NRN AL WILL DESTABILIZE GRADUALLY AHEAD OF THE STORMS AND SHOULD SUPPORT SFC-BASED STORMS. HTX HODOGRAPH SHOWS 40+ KT SFC-1KM SHEAR DESPITE A VEERED FLOW REGIME. ALONG WITH THE THREAT FOR DAMAGING WINDS...TORNADOES WILL BE POSSIBLE ALONG WITH HAIL. GIVEN INCREASING RISK FOR SEVERE...A WW WILL LIKELY BE REQUIRED BY 07Z FOR NRN AL. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN... 34888796 34878569 33788549 33808811 WWWW From MCD at goshenarc.org Mon Apr 3 07:17:19 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 03:17:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030716 SWOMCD SPC MCD 030716 NCZ000-SCZ000-TNZ000-GAZ000-030845- MESOSCALE DISCUSSION 0414 NWS STORM PREDICTION CENTER NORMAN OK 0216 AM CDT MON APR 03 2006 AREAS AFFECTED...SRN APPALACHIANS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 030716Z - 030845Z A DAMAGING WIND/HAIL THREAT MAY INCREASE ACROSS WRN NC...UPSTATE SC AND PARTS OF NRN GA AFTER 08-09Z. AS A RESULT...A WW MAY BECOME REQUIRED...STAYING N OF THE ATLANTA METRO AREA. A SW-NE ORIENTED LINE OF TSTMS CONTINUES TO SETTLE ESEWD ACROSS ERN/SRN TN THIS MORNING WITH COLD POOL DYNAMICS INCREASING. TSTMS ARE EMBEDDED IN A STRONG WSWLY UNIDIRECTIONAL FLOW REGIME. THIS WILL CONTINUE TO BE FAVORABLE FOR LINE SEGMENTS TO BOW WITH LOCAL ACCELERATION OF WIND GUSTS...PARTICULARLY ACROSS NRN GA WHERE AIR MASS IS A LITTLE MORE UNSTABLE THAN FARTHER NE. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 34878535 35688366 36008207 35728160 34928175 34158443 34068526 WWWW From MCD at goshenarc.org Mon Apr 3 07:59:19 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 03:59:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 030757 SWOMCD SPC MCD 030757 MSZ000-030900- MESOSCALE DISCUSSION 0415 NWS STORM PREDICTION CENTER NORMAN OK 0257 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN MS CONCERNING...TORNADO WATCH 141... VALID 030757Z - 030900Z WT 151 IS SET TO EXPIRE AT 09Z AND TSTMS SHOULD MOVE OUT OF THE WATCH BY THEN. THERE WILL BE AN ISOLD DAMAGING WIND/HAIL/TORNADO THREAT DOWNSTREAM INTO PARTS OF NRN MS NEAR/N OF KGTR BETWEEN 0830-0900Z JUST S OF THE CURRENT WATCH. WRN PORTION OF THE SW-NE ORIENTED LINE OF STORMS WAS BEGINNING TO WEAKEN ACROSS SERN AR AND NWRN MS EARLY THIS MORNING. HOWEVER...STRONG TSTMS CONTINUE ACROSS NCNTRL-NERN MS EWD INTO NRN AL. TSTMS ARE EMBEDDED IN A FAST UNIDIRECTIONAL WSWLY FLOW REGIME AND COULD BECOME FAVORABLY ALIGNED TO PRODUCE DAMAGING WINDS AS THEY MOVE ESEWD TOWARD AREAS NEAR/N OF KGTR. OTHERWISE...ACCAS BAND AHEAD OF THE LINE WAS BEGINNING TO SPROUT INTO TSTMS ACROSS CNTRL MS NEWD INTO NCNTRL AL. THESE STORMS ARE DEVELOPING IN A STRONG WARM ADVECTION REGIME. THOUGH THEY MAY TEND TO BE ELEVATED /LARGE HAIL THREAT/...THEY COULD ROOT INTO THE BOUNDARY LAYER AND BEGIN TO PRODUCE DAMAGING WINDS...PARTICULARLY AS THEY MOVE INTO CNTRL/NRN AL. CURRENT INDICATIONS ARE THAT ANOTHER WW WILL NOT BE REQUIRED ACROSS CNTRL MS GIVEN THAT MAJORITY OF THE MASS CONVERGENCE IS POINTING MORE TOWARD THE SRN APPALACHIANS. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...JAN... 33799039 34248855 33918833 33418843 33078977 WWWW From MCD at goshenarc.org Mon Apr 3 10:13:25 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 06:13:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031010 SWOMCD SPC MCD 031010 NCZ000-SCZ000-GAZ000-TNZ000-ALZ000-031215- MESOSCALE DISCUSSION 0416 NWS STORM PREDICTION CENTER NORMAN OK 0510 AM CDT MON APR 03 2006 AREAS AFFECTED...CNTRL/ERN AL...NRN/CNTRL GA...WRN SC...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031010Z - 031215Z HIGHEST PROBABILITY FOR LARGE HAIL...DAMAGING WINDS...AND PERHAPS A TORNADO OR TWO WILL EXIST ACROSS ECNTRL AL NEWD ACROSS CNTRL/NRN GA THROUGH MID-MORNING. A STRONG MID-LEVEL JET STREAK CONTINUED TO TRANSLATE EWD ACROSS THE MID-SOUTH AT DAYBREAK...WITH THE STRONGEST LARGE SCALE ASCENT SPREADING INTO THE SRN APPALACHIANS. THE TSTMS THAT GREW UPSCALE INTO A LINEAR MCS OVERNIGHT...CONTINUE TO MOVE ESEWD ACROSS THE SRN APPALACHIANS AT 10Z. DESPITE STRONG LOW/MID-LEVEL SHEAR...COLD OUTFLOW HAS TENDED TO DOMINATE THE STORMS THROUGH THE MORNING...LESSENING THE RISK FOR TORNADOES. BUT...PLUME OF STEEP MID-TROPOSPHERIC LAPSE RATES SPREADING EWD FROM THE HIGH PLAINS WAS SUPPORTING LARGE HAIL. AS THE MID-LEVEL JET STREAK DEVELOPS EWD THROUGH THE MID-MORNING HOURS...TSTMS SHOULD INTENSIFY ACROSS NRN/CNTRL GA AND MOVE EWD INTO PARTS OF SC. INCREASED BOUNDARY LAYER HEATING WILL BOOST BUOYANCY AND TSTMS MAY BEGIN TO POSE MORE OF A DAMAGING WIND/TORNADO THREATS IN A FEW HOURS. STRONG WSWLY UNIDIRECTIONAL FLOW REGIME WILL ENCOURAGE BOW ECHOES AND SUPERCELLS. UPSTREAM...TSTMS WILL TEND TO BACKBUILD INTO PARTS OF AL INTO THE STEEPER MID-LEVEL LAPSE RATES. THESE STORMS WILL TEND TO BE MORE OF A LARGE HAIL THREAT. ..RACY.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...GSP...MRX...FFC...BMX... 33118830 34098574 34978471 35348281 35878187 35858054 34558096 33758171 32188322 32018566 WWWW From MCD at goshenarc.org Mon Apr 3 13:35:10 2006 From: MCD at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 09:35:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031334 SWOMCD SPC MCD 031334 NCZ000-SCZ000-031500- MESOSCALE DISCUSSION 0417 NWS STORM PREDICTION CENTER NORMAN OK 0834 AM CDT MON APR 03 2006 AREAS AFFECTED...NC...SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031334Z - 031500Z A LINE OF ELEVATED THUNDERSTORMS IS CURRENTLY ONGOING IN THE FOOTHILLS OF THE APPALACHIAN MTNS IN CNTRL NC. AS THE LINE GRADUALLY INTENSIFIES OVER THE NEXT FEW HOURS...THE THREAT FOR LARGE HAIL AND ISOLATED WIND DAMAGE WILL LIKELY INCREASE. A NEW WW MAY BECOME NECESSARY BY 14 TO 15Z. WATER VAPOR IMAGERY CURRENTLY SHOWS A POTENT UPPER-LEVEL TROUGH MOVING EWD INTO THE REGION WITH THE RUC GRADUALLY INCREASING LARGE-SCALE ASCENT OVER THE NEXT FEW HOURS ACROSS THE CAROLINAS. THIS SHOULD CONTINUE TO SUPPORT AN INCREASE IN STORM COVERAGE WITH STORMS EXPANDING SWD WITH TIME. THE GSO 12Z SOUNDING HAS SOME INSTABILITY MAINLY ABOVE 700 MB WITH LAPSE RATES FROM 700-500 MB LAPSE RATES EXCEEDING 7.0 C/KM. AS SFC HEATING CONTINUES AHEAD OF THE LINE THIS MORNING...LAPSE RATES SHOULD CONTINUE TO STEEPEN. THIS COMBINED WITH MODERATE VERTICAL SHEAR AND INCREASING INSTABILITY SHOULD RESULT IN A POTENTIAL FOR LARGE HAIL. AS THE CONVECTION MOVES EWD AND BECOMES MORE SFC-BASED AROUND MID-DAY...THERE WILL BE AN INCREASING THREAT FOR WIND DAMAGE AND TORNADOES. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CAE...GSP... 36217813 36007746 35597730 35117762 34277905 33588048 33648121 34098159 34488147 35348000 35987888 WWWW From Mcd at goshenarc.org Mon Apr 3 14:05:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 10:05:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031404 SWOMCD SPC MCD 031404 PAZ000-WVZ000-OHZ000-031530- MESOSCALE DISCUSSION 0418 NWS STORM PREDICTION CENTER NORMAN OK 0904 AM CDT MON APR 03 2006 AREAS AFFECTED...ERN PA...NRN WV...WRN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031404Z - 031530Z THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS SRN OH. AS THE STORMS EXPAND AND MOVE NEWD...A LARGE HAIL...WIND DAMAGE AND ISOLATED TORNADO THREAT WILL LIKELY DEVELOP OVER THE NEXT FEW HOURS. A WW SHOULD BECOME NECESSARY LATER THIS MORNING ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LOW OVER SRN MI WITH A POTENT TROUGH EXTENDING SWD ACROSS THE OH RIVER VALLEY. A STRONG BAND OF LARGE-SCALE ASCENT ASSOCIATED WITH THE TROUGH WILL SPREAD NEWD ACROSS ERN OH INTO WRN PA LATE THIS MORNING ALLOWING FOR THUNDERSTORM ACTIVITY TO EXPAND IN COVERAGE. OTHER STORMS SHOULD INITIATE ACROSS SW OH AND SPREAD EWD ACROSS THE SRN OH LATE THIS MORNING. VISIBLE IMAGERY SHOWS PARTIALLY CLEAR SKIES EXTENDING NNEWD FROM NRN KY ACROSS ERN OH WHICH SHOULD ALLOW FOR QUICK DESTABILIZATION THIS MORNING. THIS COMBINED WITH STEEP LAPSE RATES...MODERATE VERTICAL SHEAR AND COLD TEMPS ALOFT SHOULD SUPPORT A THREAT FOR SUPERCELLS WITH LARGE HAIL. AS THE STORMS INTENSIFY AND LOW-LEVEL LAPSE RATES STEEPEN...WIND DAMAGE AND AN AND ISOLATED TORNADO THREAT WILL BECOME POSSIBLE. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...PBZ...RLX...CLE...ILN... 40608289 41088201 41618002 41867894 41297817 40467812 39598023 39248190 39438268 40138297 WWWW From Mcd at goshenarc.org Mon Apr 3 14:25:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 10:25:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031424 SWOMCD SPC MCD 031424 COR PAZ000-MDZ000-WVZ000-OHZ000-031530- MESOSCALE DISCUSSION 0418 NWS STORM PREDICTION CENTER NORMAN OK 0924 AM CDT MON APR 03 2006 AREAS AFFECTED...ERN OH...NRN WV...WRN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031424Z - 031530Z CORRECTED FOR STATE LIST AT TOP THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS SRN OH. AS THE STORMS EXPAND AND MOVE NEWD...A LARGE HAIL...WIND DAMAGE AND ISOLATED TORNADO THREAT WILL LIKELY DEVELOP OVER THE NEXT FEW HOURS. A WW SHOULD BECOME NECESSARY LATER THIS MORNING ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN UPPER-LOW OVER SRN MI WITH A POTENT TROUGH EXTENDING SWD ACROSS THE OH RIVER VALLEY. A STRONG BAND OF LARGE-SCALE ASCENT ASSOCIATED WITH THE TROUGH WILL SPREAD NEWD ACROSS ERN OH INTO WRN PA LATE THIS MORNING ALLOWING FOR THUNDERSTORM ACTIVITY TO EXPAND IN COVERAGE. OTHER STORMS SHOULD INITIATE ACROSS SW OH AND SPREAD EWD ACROSS THE SRN OH LATE THIS MORNING. VISIBLE IMAGERY SHOWS PARTIALLY CLEAR SKIES EXTENDING NNEWD FROM NRN KY ACROSS ERN OH WHICH SHOULD ALLOW FOR QUICK DESTABILIZATION THIS MORNING. THIS COMBINED WITH STEEP LAPSE RATES...MODERATE VERTICAL SHEAR AND COLD TEMPS ALOFT SHOULD SUPPORT A THREAT FOR SUPERCELLS WITH LARGE HAIL. AS THE STORMS INTENSIFY AND LOW-LEVEL LAPSE RATES STEEPEN...WIND DAMAGE AND AN AND ISOLATED TORNADO THREAT WILL BECOME POSSIBLE. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...LWX...PBZ...RLX...CLE...ILN... 40107790 39267984 38808170 38778282 38798299 39548345 40498348 41128204 41618002 41867894 41297817 40467812 WWWW From Mcd at goshenarc.org Mon Apr 3 15:57:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 11:57:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031556 SWOMCD SPC MCD 031555 SCZ000-GAZ000-ALZ000-031800- MESOSCALE DISCUSSION 0419 NWS STORM PREDICTION CENTER NORMAN OK 1055 AM CDT MON APR 03 2006 AREAS AFFECTED...NRN GA...SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031555Z - 031800Z THUNDERSTORM INITIATION APPEARS LIKELY EARLY THIS AFTERNOON ACROSS NRN GA AND/OR FAR NE AL. AS STORMS DEVELOP...SUPERCELLS WILL HAVE A POTENTIAL FOR LARGE HAIL AND WIND DAMAGE WITH TORNADOES BECOMING INCREASINGLY POSSIBLE AS STORMS DRIFT EWD INTO ERN GA AND WRN SC. A WW WILL LIKELY BE NECESSARY AROUND MIDDAY AS STORMS INITIATE AND INCREASE IN COVERAGE. WATER VAPOR IMAGERY CURRENTLY SHOWS A POTENT UPPER-LEVEL TROUGH OVER THE TN VALLEY WITH RUC FORECASTS MOVING A STRONG VORTICITY MAX EWD ACROSS NRN GA OVER THE NEXT FEW HOURS. AS LARGE-SCALE ASCENT INCREASES...MODERATE INSTABILITY DEVELOPS ACROSS THE REGION AND LOW-LEVEL CONVERGENCE BECOMES ENHANCED...STORM INITIATION SHOULD OCCUR IN NRN GA AND/OR FAR NE AL. INITIALLY STORM DEVELOPMENT SHOULD OCCUR IN THE HIGHER TERRAIN NORTH OF ATLANTA BUT ADDITIONAL STORMS MAY INITIATE FURTHER SOUTH IN NCNTRL GA. FORECAST SOUNDINGS IN NRN GA FOR THIS AFTERNOON SHOW STRONG VERTICAL SHEAR PROFILES AND STEEP LAPSE RATES SUGGESTING SUPERCELLS WITH LARGE HAIL AND WIND DAMAGE WILL BE LIKELY. IN ADDITION...STRONG LOW-LEVEL SPEED SHEAR ASSOCIATED WITH A 40 KT LOW-LEVEL JET SHOULD BE FAVORABLE FOR TORNADOES AS SUPERCELLS MATURE AND MOVE EWD INTO ERN GA AND WRN SC LATER THIS AFTERNOON. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...CAE...GSP...FFC...BMX...HUN... 33188073 33018174 33128367 33398514 33978568 34568569 34818518 34808404 34488081 33318062 WWWW From Mcd at goshenarc.org Mon Apr 3 18:17:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:17:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031815 SWOMCD SPC MCD 031814 PAZ000-NYZ000-MDZ000-WVZ000-VAZ000-OHZ000-032015- MESOSCALE DISCUSSION 0420 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR SERN OH...WRN AND CENTRAL PA...SWRN NY AND ERN/CENTRAL WV...NWRN VA...PANDHANDLE OF MD CONCERNING...TORNADO WATCH 146... VALID 031814Z - 032015Z ORGANIZED LINE OF CONVECTION MOVING THROUGH WRN PA WILL CONTINUE TO POSE A THREAT FOR MAINLY DMGG WINDS OVER THE NEXT FEW HRS. AN ISOLATED TORNADO IS ALSO POSSIBLE WITHIN THIS LINE. FURTHER SW..MORE CELLULAR CONVECTION OVER CENTRAL WV AND FAR SERN OH SHOULD CONTINUE TO GRADUALLY INTENSIFY AND MAY BEGIN TO POSE A THREAT FOR ISOLATED TORNADOES AND SVR WINDS/HAIL. AREAS DOWNWIND OF TORNADO WW 146...CENTRAL PA AND ERN WV/WRN MD/VA...WILL BE MONITORED FOR DESTABILIZING TRENDS OVER THE NEXT COUPLE HRS. LATEST RADAR DATA SHOWS AN ORGANIZED LINE OF STG-SVR STORMS OVER WRN PA MOVING ENEWD AROUND 30 KTS. EXTRAPOLATION OF THIS LINE MOTION TAKE THE LINE OUT OF WW 146 INTO CENTRAL PA AROUND 19Z. ATTM THE AIRMASS DOWNSTREAM OVER CENTRAL PA IS ONLY MARGINALLY UNSTABLE WITH MUCAPES FROM 100-300 J/KG AND TEMPERATURES IN THE 50S. RECENT VISIBLE SATELLITE TRENDS AND CURRENT FCST SOUNDINGS INDICATE THAT INSTABILITY SHOULD NOT INCREASE SUBSTANTIALLY IN THIS AREA AHEAD OF THE CONVECTIVE LINE. THIS SHOULD AID IN A DECREASING TREND IN THE SEVERITY OF THE CONVECTIVE LINE AS IT MOVES INTO CENTRAL PA. FURTHER NORTH...SLIGHTLY HIGHER INSTABILITY OVER SWRN NY MAY SUPPORT A MARGINAL SVR THREAT WITH CONVECTIVE LINE OVER THE NEXT FEW HRS. FURTHER SOUTH...WLY FLOW INCREASING OVER THE CENTRAL APPALACHIANS HAS LEAD TO SUBSIDENCE AND DRYING OVER THE LOWER ELEVATIONS OF ERN WV AND NWRN VA. CONVECTION THAT WAS INTENSIFYING OVER CENTRAL WV MAY TEND TO WEAKEN SOME AS IT MOVES INTO THIS WEAKER INSTABILITY AREA AND OUT OF WW 146. WE WILL MONITOR TRENDS FOR THE NEED FOR AN ADDITIONAL WATCH IN THIS AREA AS WELL. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BGM...BUF...CTP...LWX...PBZ...RLX...CLE... 42027747 43157833 42947907 42387988 41998062 41478092 40348104 39118120 38858111 38428096 38268017 38357872 39267785 40417755  From Mcd at goshenarc.org Mon Apr 3 18:38:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:38:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031836 SWOMCD SPC MCD 031836 NCZ000-VAZ000-032030- MESOSCALE DISCUSSION 0421 NWS STORM PREDICTION CENTER NORMAN OK 0136 PM CDT MON APR 03 2006 AREAS AFFECTED...SRN VA...NRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031836Z - 032030Z STORM INITIATION WILL BECOME INCREASINGLY LIKELY FROM NRN NC INTO SRN VA AS DESTABILIZATION OCCURS THIS AFTERNOON. THE ENVIRONMENT WILL BECOME FAVORABLE FOR SUPERCELLS WITH A POTENTIAL FOR TORNADOES...LARGE HAIL AND WIND DAMAGE. A WW MAY BE NEEDED BY MID TO LATE AFTERNOON ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS A STRONG UPPER-LEVEL TROUGH ENTERING THE APPALACHIAN MTNS. LARGE-SCALE ASCENT WILL MARKEDLY INCREASE AS THE TROUGH BEGINS TO AFFECT THE FOOTHILLS OF VA AND NC THIS AFTERNOON. IN ADDITION...VISIBLE IMAGERY SHOWS CUMULUS BEGINNING TO FORM ALONG A MESOSCALE THERMAL AXIS EXTENDING NWD FROM GREENSBORO NC TO ROANOKE VA. ALTHOUGH THE AREA REMAINS CAPPED AND WEAKLY UNSTABLE...DESTABILIZATION WILL CONTINUE DUE TO SFC HEATING. IN ADDITION...LOW-LEVEL CONVERGENCE SHOULD BECOME ENHANCED LATE THIS AFTERNOON WHICH COMBINED INCREASING ASCENT FROM THE WEST SHOULD SUPPORT STORM INITIATION. INITIATION WOULD BE MOST LIKELY ALONG THE THERMAL AXIS IN THE 20Z TO 22Z TIMEFRAME. CLEARING ON VISIBLE IMAGERY SHOULD ALLOW MODERATE INSTABILITY TO DEVELOP BY LATE AFTERNOON WHICH COMBINED WITH 50 KT OF VERTICAL SHEAR WILL BE FAVORABLE FOR SUPERCELLS. IN ADDITION...A 40 KT LOW-LEVEL JET CURRENTLY FORMING OVER NRN NC EVIDENT ON OBJECTIVE ANALYSIS COMBINED WITH BACKED SFC WINDS ALONG THE NC-VA STATE-LINE WILL BE INCREASINGLY FAVORABLE FOR TORNADOES AS SUPERCELLS DEVELOP AND TRACK EWD INTO SE VA AND NE NC BY EARLY THIS EVENING. LARGE HAIL AND WIND DAMAGE WILL ALSO BE LIKELY WITH SUPERCELLS AS LAPSE RATES STEEPEN DUE TO THE APPROACH OF THE UPPER-LEVEL TROUGH. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...GSP... 35347698 35117848 35227996 35768049 36148061 36778064 37198032 37557918 37557731 37377641 36837607 36217602 35727610  From Mcd at goshenarc.org Mon Apr 3 18:45:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 14:45:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 031842 SWOMCD SPC MCD 031842 TXZ000-032045- MESOSCALE DISCUSSION 0422 NWS STORM PREDICTION CENTER NORMAN OK 0142 PM CDT MON APR 03 2006 AREAS AFFECTED...SCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 031842Z - 032045Z TOWERING CU WAS DEVELOPING ALONG A STATIONARY BOUNDARY OVER SCENTRAL TX FROM THE DRT AREA EWD TO NEAR SAT AND AUS AREA. MODERATE-STG INSTABILITY WILL AID IN POTENTIAL FOR ISOLATED SVR WIND/HAIL... DESPITE MARGINAL VERTICAL WIND SHEAR. LATEST SFC ANALYSIS INDICATES A STATIONARY FRONT EXTENDING FROM NEAR DRT EWD TO JUST SOUTH OF KERRVILLE EWD TO BASTROP COUNTY. MODERATE INSTABILITY WITH MLCAPES AROUND 2000 J/KG EXISTED ALONG AND SOUTH OF THIS BOUNDARY. ALTHOUGH CONVERGENCE IS RELATIVELY WEAK ALONG THE BOUNDARY...CONTINUED DAYTIME HEATING SHOULD AID IN AT LEAST AN ISOLATED TSTM DEVELOPMENT. GIVEN THE DEGREE OF INSTABILITY AND STEEP LOW-MID LVL LAPSE RATES...THERE WILL BE SOME POTENTIAL FOR ISOLATED SVR HAIL/WIND AS STORMS MOVE SEWD AROUND 15 KTS. RELATIVELY WEAK MID LEVEL WINDS WILL BE SOMEWHAT OFFSET BY ELY LOW LEVEL WINDS...ENHANCING VERTICAL SHEAR. HOWEVER...SHEAR SHOULD REMAIN LOW ENOUGH THAT AN ORGANIZED SVR THREAT IS NOT ANTICIPATED. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842  From Mcd at goshenarc.org Mon Apr 3 21:00:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 17:00:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032059 SWOMCD SPC MCD 032059 NCZ000-SCZ000-032230- MESOSCALE DISCUSSION 0423 NWS STORM PREDICTION CENTER NORMAN OK 0359 PM CDT MON APR 03 2006 AREAS AFFECTED...NRN SC AND CNTRL NC CONCERNING...SEVERE THUNDERSTORM WATCH 147... VALID 032059Z - 032230Z SEVERAL SUPERCELLS ARE ONGOING ACROSS THE ERN PART OF WW 147. LARGE HAIL AND WIND DAMAGE WILL BE LIKELY WITH THE STORMS OVER THE NEXT FEW HOURS. TORNADOES WILL ALSO BE POSSIBLE WITH THE STRONGER SUPERCELLS AS THE STORMS TRACK EWD INTO NERN SC AND SCNTRL NC BY EARLY EVENING. WATER VAPOR IMAGERY AND RUC ANALYSIS CURRENTLY SHOW A STRONG VORTICITY MAX IN NRN VA WITH A BAND OF WELL-FOCUSED LARGE-SCALE ASCENT MOVING ACROSS THE WRN CAROLINAS ATTM. THE SUPERCELLS ARE ONGOING ALONG THE LEADING EDGE OF ASCENT JUST AHEAD OF A 70 KT MID-LEVEL JET. THE LIFT COMBINED WITH STEEPENING LAPSE RATES AND THE RELATIVELY DRY BOUNDARY LAYER (SFC DEWPOINTS IN THE 40S F) WILL FAVOR WIND DAMAGE AND LARGE HAIL. THE WIND DAMAGE POTENTIAL WILL BE ENHANCED WEST OF I-77 WHERE SFC TEMP-DEWPOINT DEPRESSIONS EXCEED 30 DEGREES F. AS THE SUPERCELLS MOVE EWD INTO NERN SC AND SCNTRL NC...THE TORNADO POTENTIAL WILL INCREASE SOME DUE TO GREATER LOW-LEVEL MOISTURE WHERE SFC DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 50S F. ..BROYLES.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...ILM...CAE...GSP... 35498158 35988112 36087935 35727868 34627859 34177968 33848103 33928134 34198188 34998197 WWWW From Mcd at goshenarc.org Mon Apr 3 23:30:53 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 19:30:53 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032330 SWOMCD SPC MCD 032329 TXZ000-040130- MESOSCALE DISCUSSION 0424 NWS STORM PREDICTION CENTER NORMAN OK 0629 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR SERN OH...WRN AND CENTRAL PA...SWRN NY AND ERN/CENTRAL WV...NWRN VA...PANDHANDLE OF MD CONCERNING...TORNADO WATCH 146... VALID 032329Z - 040130Z ORGANIZED LINE OF CONVECTION MOVING THROUGH WRN PA WILL CONTINUE TO POSE A THREAT FOR MAINLY DMGG WINDS OVER THE NEXT FEW HRS. AN ISOLATED TORNADO IS ALSO POSSIBLE WITHIN THIS LINE. FURTHER SW..MORE CELLULAR CONVECTION OVER CENTRAL WV AND FAR SERN OH SHOULD CONTINUE TO GRADUALLY INTENSIFY AND MAY BEGIN TO POSE A THREAT FOR ISOLATED TORNADOES AND SVR WINDS/HAIL. AREAS DOWNWIND OF TORNADO WW 146...CENTRAL PA AND ERN WV/WRN MD/VA...WILL BE MONITORED FOR DESTABILIZING TRENDS OVER THE NEXT COUPLE HRS. LATEST RADAR DATA SHOWS AN ORGANIZED LINE OF STG-SVR STORMS OVER WRN PA MOVING ENEWD AROUND 30 KTS. EXTRAPOLATION OF THIS LINE MOTION TAKE THE LINE OUT OF WW 146 INTO CENTRAL PA AROUND 19Z. ATTM THE AIRMASS DOWNSTREAM OVER CENTRAL PA IS ONLY MARGINALLY UNSTABLE WITH MUCAPES FROM 100-300 J/KG AND TEMPERATURES IN THE 50S. RECENT VISIBLE SATELLITE TRENDS AND CURRENT FCST SOUNDINGS INDICATE THAT INSTABILITY SHOULD NOT INCREASE SUBSTANTIALLY IN THIS AREA AHEAD OF THE CONVECTIVE LINE. THIS SHOULD AID IN A DECREASING TREND IN THE SEVERITY OF THE CONVECTIVE LINE AS IT MOVES INTO CENTRAL PA. FURTHER NORTH...SLIGHTLY HIGHER INSTABILITY OVER SWRN NY MAY SUPPORT A MARGINAL SVR THREAT WITH CONVECTIVE LINE OVER THE NEXT FEW HRS. FURTHER SOUTH...WLY FLOW INCREASING OVER THE CENTRAL APPALACHIANS HAS LEAD TO SUBSIDENCE AND DRYING OVER THE LOWER ELEVATIONS OF ERN WV AND NWRN VA. CONVECTION THAT WAS INTENSIFYING OVER CENTRAL WV MAY TEND TO WEAKEN SOME AS IT MOVES INTO THIS WEAKER INSTABILITY AREA AND OUT OF WW 146. WE WILL MONITOR TRENDS FOR THE NEED FOR AN ADDITIONAL WATCH IN THIS AREA AS WELL. ..CROSBIE.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842 WWWW From Mcd at goshenarc.org Mon Apr 3 23:34:54 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 19:34:54 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 032333 SWOMCD SPC MCD 032333 SCZ000-NCZ000-GAZ000-040000- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 0633 PM CDT MON APR 03 2006 AREAS AFFECTED...WRN AND CENTRAL CAROLINAS CONCERNING...TORNADO WATCH 147... VALID 032333Z - 040000Z STRONGER STORMS CONTINUE MOVING EWD OUT OF ERN PORTIONS OF WW 147 INTO WW 148...WHILE CONVECTION FURTHER W INTO WW 147 CONTINUES TO WEAKEN. THEREFORE...WW 147 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 04/00Z. SEVERE THREAT ACROSS WW 147 CONTINUES TO DIMINISH...AS WLY SURFACE WINDS ARE ADVECTING MUCH DRIER/MORE STABLE BOUNDARY LAYER EWD ACROSS WRN PORTIONS OF THE NC/SC. MOST UNSTABLE AIRMASS REMAINS ACROSS THE ERN CAROLINAS...WHERE WW 148 IS NOW IN EFFECT. THOUGH A FEW SEVERE STORMS MAY PERSIST FOR A COUPLE OF HOURS ACROSS SERN SC -- S OF WW 148 AND SE OF WW 147...AREA OF THREAT REMAINS SMALL. THEREFORE...LIMITED TEMPORAL AND SPATIAL EXTENT OF THREAT AREA PRECLUDES THE NEED FOR A NEW WW. ..GOSS.. 04/03/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...ILM...RNK...CAE...GSP...FFC... 33638252 35938128 36098053 34307982 WWWW From Mcd at goshenarc.org Tue Apr 4 00:21:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 20:21:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040020 SWOMCD SPC MCD 040019 TXZ000-040215- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 0719 PM CDT MON APR 03 2006 AREAS AFFECTED...SCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 040019Z - 040215Z TOWERING CU WAS DEVELOPING ALONG A STATIONARY BOUNDARY OVER SCENTRAL TX FROM THE DRT AREA EWD TO NEAR SAT AND AUS AREA. MODERATE-STG INSTABILITY WILL AID IN POTENTIAL FOR ISOLATED SVR WIND/HAIL... DESPITE MARGINAL VERTICAL WIND SHEAR. LATEST SFC ANALYSIS INDICATES A STATIONARY FRONT EXTENDING FROM NEAR DRT EWD TO JUST SOUTH OF KERRVILLE EWD TO BASTROP COUNTY. MODERATE INSTABILITY WITH MLCAPES AROUND 2000 J/KG EXISTED ALONG AND SOUTH OF THIS BOUNDARY. ALTHOUGH CONVERGENCE IS RELATIVELY WEAK ALONG THE BOUNDARY...CONTINUED DAYTIME HEATING SHOULD AID IN AT LEAST AN ISOLATED TSTM DEVELOPMENT. GIVEN THE DEGREE OF INSTABILITY AND STEEP LOW-MID LVL LAPSE RATES...THERE WILL BE SOME POTENTIAL FOR ISOLATED SVR HAIL/WIND AS STORMS MOVE SEWD AROUND 15 KTS. RELATIVELY WEAK MID LEVEL WINDS WILL BE SOMEWHAT OFFSET BY ELY LOW LEVEL WINDS...ENHANCING VERTICAL SHEAR. HOWEVER...SHEAR SHOULD REMAIN LOW ENOUGH THAT AN ORGANIZED SVR THREAT IS NOT ANTICIPATED. ..CROSBIE.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 29969952 29660102 29230093 29000008 28939850 29609713 30209684 30049842 WWWW From Mcd at goshenarc.org Tue Apr 4 01:17:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 21:17:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040116 SWOMCD SPC MCD 040116 VAZ000-DEZ000-MDZ000-PAZ000-NCZ000-SCZ000-040245- MESOSCALE DISCUSSION 0424 NWS STORM PREDICTION CENTER NORMAN OK 0816 PM CDT MON APR 03 2006 AREAS AFFECTED...ERN MD/ERN VA/ERN NC/NERN SC CONCERNING...TORNADO WATCH 148... VALID 040116Z - 040245Z LINE OF STRONG/SEVERE STORMS CONTINUES MOVING EWD ACROSS WW. LATEST RADAR IMAGERY SHOWS LINE OF STRONG TO LOCALLY SEVERE THUNDERSTORMS EXTENDING FROM THE DELMARVA REGION SSWWD INTO ERN NC. MEANWHILE...A SECOND CLUSTER OF STORMS CONTINUES MOVING ACROSS COASTAL PORTIONS OF NC AND THE NERN SC COAST. STORMS OVER E CENTRAL AND NERN VA CONTINUE TO MOVE EWD INTO COOLER/MORE STABLE BOUNDARY LAYER...AS SELY SURFACE WINDS CONTINUE TO ADVECT ATLANTIC AIR INLAND. THEREFORE...EXPECT STORMS TO WEAKEN WITH TIME...WITH ONLY A MARGINAL HAIL THREAT LIKELY TO LINGER AS STORMS MOVE OUT OF THE NERN CORNER OF WW 148 AND EVENTUALLY OFF THE NJ/DE COASTS. FURTHER S INTO SERN VA/ERN NC/NERN SC...POCKETS OF MODERATE INSTABILITY REMAIN. WITH STRONGEST MID-LEVEL FLOW ACROSS THE ERN CAROLINAS ATTM...DEEP-LAYER SHEAR REMAINS SUFFICIENT FOR LOCALLY SEVERE/SUPERCELL STORMS. THEREFORE...EXPECT SEVERE THREAT TO LINGER FOR A COUPLE MORE HOURS -- PARTICULARLY ACROSS ERN NC WHERE STORMS SHOULD REMAIN ONSHORE THE LONGEST. ..GOSS.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...MHX...CTP...LWX...RAH...ILM...CAE... 33637997 35267983 36727737 38267643 39737667 39737562 33677649 WWWW From Mcd at goshenarc.org Tue Apr 4 03:02:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 03 Apr 2006 23:02:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 040302 SWOMCD SPC MCD 040301 NCZ000-SCZ000-040400- MESOSCALE DISCUSSION 0425 NWS STORM PREDICTION CENTER NORMAN OK 1001 PM CDT MON APR 03 2006 AREAS AFFECTED...FAR NERN SC/SERN NC CONCERNING...TORNADO WATCH 148... VALID 040301Z - 040400Z SEVERE THREAT CONTINUES TO DECREASE. WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 04/04Z. LATEST RADAR LOOP SHOWS MOST CONVECTION WEAKENING/MOVING OFFSHORE ATTM. GREATEST INSTABILITY -- AND THUS LINGERING SEVERE THREAT -- IS INDICATED ACROSS FAR NERN SC AND SERN NC...WHERE STRONGEST STORMS ARE INDICATED. THOUGH LIMITED/LOCAL SEVERE THREAT MAY PERSIST FOR THE NEXT 1-2 HOURS ACROSS A FEW COUNTIES IN THIS AREA...STORMS SHOULD CONTINUE TO GENERALLY WEAKEN AND MOVE OFFSHORE WITH TIME. ..GOSS.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...ILM... 33667930 34567810 35287761 35137630 33677649 WWWW From Mcd at goshenarc.org Tue Apr 4 16:43:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 12:43:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 041642 SWOMCD SPC MCD 041642 CAZ000-041845- MESOSCALE DISCUSSION 0426 NWS STORM PREDICTION CENTER NORMAN OK 1142 AM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL CA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 041642Z - 041845Z THUNDERSTORM INITIATION WILL BE LIKELY ACROSS THE SAN JOAQUIN VALLEY AND SCNTRL COAST THIS AFTERNOON. THE STRONGER STORMS WILL HAVE A POTENTIAL FOR LARGE HAIL AND A WW MAY BECOME NECESSARY. LATEST SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING FROM THE SANTA BARBARA VICINITY NWD ACROSS THE SAN JOAQUIN VALLEY WITH DEWPOINTS IN THE MID 50S F. PARTIAL CLEARING IS EVIDENT ON VISIBLE IMAGERY OVER THE VALLEY WHERE TEMPS HAVE WARMED TO NEAR 60 F. ADDITIONAL DESTABILIZATION COMBINED WITH STRONG VERTICAL SHEAR WILL BE FAVORABLE FOR ROTATING STORMS. COLD AIR ALOFT ASSOCIATED WITH AN APPROACHING VIGOROUS UPPER-LEVEL TROUGH WILL CONTINUE TO STEEPEN LAPSE RATES OVER CNTRL CA THIS AFTERNOON WITH THE THREAT FOR LARGE HAIL GRADUALLY INCREASING. ISOLATED WIND DAMAGE AND/OR BRIEF TORNADOES MAY ALSO BECOME POSSIBLE AS SFC HEATING FURTHER DESTABILIZES THE AIR MASS ..BROYLES.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HNX...LOX...STO...MTR... 35631972 35602061 35702115 35872147 36342152 37242145 38062116 38122031 37881956 37201942 WWWW From Mcd at goshenarc.org Tue Apr 4 18:32:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 14:32:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 041831 SWOMCD SPC MCD 041831 FLZ000-042030- MESOSCALE DISCUSSION 0427 NWS STORM PREDICTION CENTER NORMAN OK 0131 PM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 041831Z - 042030Z SCATTERED THUNDERSTORMS SHOULD DEVELOP THIS AFTERNOON ALONG A SFC BOUNDARY ACROSS CNTRL FL. THE STRONGER CELLS WILL HAVE A POTENTIAL FOR HAIL AND DAMAGING WIND GUSTS. LATEST SFC ANALYSIS SHOWS A SLOW MOVING COLD FRONT EXTENDING EWD FROM TAMPA BAY ACROSS THE CNTRL PENINSULA. SFC DEWPOINTS ALONG AND SOUTH OF THE BOUNDARY ARE IN THE MID 60S F AND MODERATE INSTABILITY HAS DEVELOPED DUE TO MOST CLEAR SKIES. VISIBLE IMAGERY SHOWS A SEA BREEZE FRONT MOVING INLAND ACROSS ERN FL AND NEW STORMS SHOULD INITIATE ALONG THE SEA BREEZE-COLD FRONTAL BOUNDARY INTERSECTION AS TEMPS CONTINUE TO WARM AND LOW-LEVEL CONVERGENCE INCREASES. FORECAST SOUNDINGS ACROSS THE CNTRL FL PENINSULA THIS AFTERNOON SHOW A WEAK TO MODERATELY SHEARED ENVIRONMENT WITH RELATIVELY STEEP LAPSE RATES. THIS SUGGESTS SEVERE MULTICELL STORMS WOULD BE FAVORED WITH A POTENTIAL FOR HAIL. IN ADDITION...STEEPENING LOW-LEVEL LAPSE RATES THIS AFTERNOON SHOULD RESULT IN A POTENTIAL FOR DAMAGING WIND GUSTS WITH THE STRONGER CELLS. ..BROYLES.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...TBW... 27248087 27018194 27128227 27528245 27868231 28138137 28138087 27488058 WWWW From Mcd at goshenarc.org Tue Apr 4 23:10:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 19:10:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 042309 SWOMCD SPC MCD 042309 UTZ000-IDZ000-NVZ000-050115- MESOSCALE DISCUSSION 0428 NWS STORM PREDICTION CENTER NORMAN OK 0609 PM CDT TUE APR 04 2006 AREAS AFFECTED...NERN NV/SRN ID CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 042309Z - 050115Z ...ISOLD SVR TSTMS WILL CONTINUE TO DEVELOP ACROSS PORTIONS OF THE SNAKE RIVER VALLEY WITH POTENTIAL FOR DAMAGING WINDS AND HAIL... LATEST RADAR LOOPS SHOW SEVERAL STORMS HAVE DEVELOPED NORTHEAST OF ELKO AND SOUTHEAST OF BOISE. BOUNDARY LAYER TEMPS HAVE INCREASED INTO THE LOWER 60S...WHICH HAS CONTRIBUTED TO MLCAPE VALUES NEAR 1000 J/KG. LARGE SCALE ASCENT HAS BEEN INCREASING ACROSS THE ENTIRE REGION ASSOCIATED WITH DIFFLUENT UPPER LEVEL TROUGH. WIND FIELDS ALOFT ARE VERY STRONG...WITH VAD WIND DATA SHOWING 40 KT WITHIN THE LOWEST 1KM AGL AT ELKO. DEEP LAYER SHEAR PROFILES /IN EXCESS OF 50KT/ WILL SUPPORT SUPERCELL STRUCTURES...AND RECENT RADAR DATA FROM BOISE HAS BEEN INDICATING LOW LEVEL ROTATION WITH STORM NEARING MOUNTAIN HOME ID. IN ADDITION TO THE THREAT OF LARGE HAIL...VERY STRONG WIND GUSTS ARE LIKELY. ..TAYLOR.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SLC...PIH...BOI...LKN...REV... 39141664 39861772 43061611 43141510 42841315 42261316 40181479 39211572 WWWW From Mcd at goshenarc.org Tue Apr 4 23:36:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 04 Apr 2006 19:36:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 042335 SWOMCD SPC MCD 042334 NVZ000-CAZ000-050030- MESOSCALE DISCUSSION 0429 NWS STORM PREDICTION CENTER NORMAN OK 0634 PM CDT TUE APR 04 2006 AREAS AFFECTED...CNTRL CA CONCERNING...SEVERE THUNDERSTORM WATCH 149... VALID 042334Z - 050030Z ...ISOLD SVR THREAT WILL CONTINUE EAST OF FRESNO/HANFORD THROUGH 02Z... LATEST RADAR TRENDS ARE BEING MONITORED ACROSS CNTRL CA...WHERE WIND FIELDS REMAIN EXTREMELY STRONG AHEAD OF APPROACHING TROUGH. STORMS HAVE INCREASED OVER THE LAST HOUR OR SO...WHERE AIRMASS HAS BECOME MARGINALLY UNSTABLE. TEMPERATURES AT 500MB ARE AT LEAST MINUS 20 CELSIUS OR BELOW AND THIS IS PROMOTING STEEP LAPSE RATES. SEVERE THREAT WILL LIKELY PERSIST BEYOND THE EXPIRATION OF WW 149 AND THE WATCH MAY NEED TO BE LOCALLY EXTENDED. SVR THREAT WILL MAINLY EXIST FOR LARGE HAIL. WINDS VEER TO WLY BEHIND CONVECTIVE LINE WHICH EXTENDS FROM NE OF FAT TO HJO...SO PRIMARY THREAT APPEARS TO REMAIN OVER PARTS OF MADERA/FRESNO/TULARE COUNTIES. ..TAYLOR.. 04/04/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...VEF...REV...HNX...STO... 35571825 35601901 36872002 37882038 38551976 38421872 36941704 36141715 WWWW From Mcd at goshenarc.org Wed Apr 5 16:55:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 12:55:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 051654 SWOMCD SPC MCD 051653 WYZ000-COZ000-NMZ000-AZZ000-UTZ000-IDZ000-051900- MESOSCALE DISCUSSION 0430 NWS STORM PREDICTION CENTER NORMAN OK 1153 AM CDT WED APR 05 2006 AREAS AFFECTED...ERN UT/WRN CO AND SW WY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 051653Z - 051900Z THUNDERSTORM DEVELOPMENT WILL CONTINUE THROUGH EARLY AFTERNOON ACROSS WRN CO...ERN UT AND SWRN WY. THE MORE INTENSE STORMS WILL HAVE A POTENTIAL FOR HAIL AND ISOLATED WIND DAMAGE. A WW WILL LIKELY BECOME NECESSARY BY THIS AFTERNOON ACROSS THE REGION. WATER VAPOR IMAGERY CURRENTLY SHOWS AN IMPRESSIVE WEST COAST UPPER-LEVEL TROUGH WITH A DRY SLOT AND BAND OF STRONG LARGE-SCALE ASCENT DRIFTING ENEWD ACROSS THE REGION. A LINE OF STORMS IS ONGOING ALONG THE LEADING EDGE OF ASCENT AND ADDITIONAL STORMS SHOULD DEVELOP ACROSS ERN UT OVER THE NEXT HOUR AS SFC TEMPS WARM TO NEAR 70 F AND ASCENT INCREASES IN THE NOSE OF A 100 KT MID-LEVEL JET. FORECAST SOUNDINGS ACROSS THE REGION THIS AFTERNOON SHOW VERY STEEP MID-LEVEL LAPSE RATES AND STRONG VERTICAL SHEAR SUGGESTING SUPERCELLS WITH HAIL POTENTIAL WILL INCREASE. IN ADDITION...SFC TEMP-DEWPOINT DEPRESSIONS WILL EXCEED 30 DEGREES F ENHANCING THE WIND DAMAGE POTENTIAL WITH THE STRONGER CELLS. ..BROYLES.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PUB...CYS...ABQ...RIW...GJT...FGZ...SLC...PIH... 36770798 36740897 37400978 38851007 40951077 41831106 42231108 42741046 42950907 42490809 41200763 40080736 38740711 38670697 37530713 37060743 WWWW From Mcd at goshenarc.org Wed Apr 5 22:00:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 18:00:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 052159 SWOMCD SPC MCD 052159 MTZ000-WYZ000-052330- MESOSCALE DISCUSSION 0431 NWS STORM PREDICTION CENTER NORMAN OK 0459 PM CDT WED APR 05 2006 AREAS AFFECTED...NRN WY INTO S-CNTRL AND SERN MT CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 052159Z - 052330Z POTENTIAL FOR LOCALLY STRONG WIND GUSTS AND PERHAPS ISOLATED LARGE HAIL WILL INCREASE ACROSS AREA LATE THIS AFTERNOON INTO EVENING. CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE WW. LATEST MESOANALYSIS INDICATED LOW PRESSURE S OF LND AND SW COD WITH ATTENDANT WARM FRONT EXTENDING ENEWD ACROSS FAR SERN MT AND THEN INTO CNTRL SD. TRAILING COLD FRONT THEN EXTENDED SWD FROM THESE LOW PRESSURE CENTERS INTO WRN CO. WELL-DEFINED RISE-FALL COUPLET FROM N-CNTRL WY INTO ERN UT SUGGESTS THAT THIS LOW PRESSURE WILL CONTINUE TO DEVELOP NEWD INTO SRN MT THIS EVENING. MODIFICATION OF 18Z RIW SOUNDING FOR CURRENT SURFACE OBSERVATIONS ACROSS N-CNTRL WY INDICATES STEEP LOW TO MID-LEVEL LAPSE RATES AND SBCAPES OF AROUND 1000 J/KG. GIVEN A DEEP AND WELL-MIXED BOUNDARY-LAYER COUPLED WITH DCAPES OF 1000-1300 J/KG...POTENTIAL WILL EXIST FOR LOCALLY STRONG DOWNDRAFTS WITH MOST INTENSE STORMS. MOREOVER...40-50 KTS OF DEEP-LAYER SHEAR ALSO SUGGESTS A THREAT OF MARGINAL SUPERCELL STRUCTURES CAPABLE OF ISOLATED LARGE HAIL. STRENGTHENING UPPER DIVERGENCE AHEAD OF EVOLVING UPPER LOW OVER THE GREAT BASIN SHOULD SUPPORT AN INCREASE IN CONVECTIVE COVERAGE LATE THIS AFTERNOON INTO EVENING ACROSS N-CNTRL/NERN WY INTO S-CNTRL AND SERN MT. PRIMARY QUESTION IS WHETHER THIS STRONGER FORCING FOR ASCENT WILL SUFFICIENTLY OFFSET A COOLING BOUNDARY-LAYER AFTER 23-00Z...SUSTAINING A SEVERE THREAT THROUGH THE EVENING. ..MEAD.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...UNR...CYS...BYZ...RIW... 43190960 44161028 45750960 46490779 46300568 44980442 43590459 42890561 42560709 WWWW From Mcd at goshenarc.org Wed Apr 5 22:42:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 18:42:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 052242 SWOMCD SPC MCD 052241 WYZ000-COZ000-NMZ000-AZZ000-UTZ000-IDZ000-052345- MESOSCALE DISCUSSION 0432 NWS STORM PREDICTION CENTER NORMAN OK 0541 PM CDT WED APR 05 2006 AREAS AFFECTED...SWRN WY / ERN UT / WRN CO CONCERNING...SEVERE THUNDERSTORM WATCH 151... VALID 052241Z - 052345Z POTENTIAL FOR LOCALLY STRONG WIND GUSTS WILL LIKELY CONTINUE BEYOND 23Z...HOWEVER AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. CLUSTERS OF TSTMS ARE ONGOING AS OF 2225Z FROM N-CNTRL NM NWD THROUGH PORTIONS OF WRN AND CNTRL CO INTO WRN AND CNTRL WY WITHIN ZONE OF STRONG LARGE-SCALE FORCING FOR ASCENT ASSOCIATED WITH UPPER LOW EVOLVING OVER THE GREAT BASIN. REGIONAL VWPS INDICATE LARGELY UNIDIRECTIONAL WIND PROFILES WITH RELATIVELY STRONG VERTICAL SPEED SHEAR...SUPPORTIVE OF ORGANIZED SEVERE TSTMS. HOWEVER...VISIBLE SATELLITE AND SURFACE OBSERVATIONS INDICATE THAT CONSIDERABLE CLOUDS AND PRECIPITATION HAVE RESULTED IN COOLING OF PRE-FRONTAL BOUNDARY-LAYER ACROSS WRN INTO CNTRL CO WHICH IS EFFECTIVELY LIMITING THE DEGREE OF INSTABILITY. THROUGH 23-01Z...IT APPEARS THE GREATEST THREAT OF LOCALLY STRONG WIND GUSTS AND/OR MARGINALLY SEVERE HAIL WILL EXIST ACROSS NRN PORTIONS OF WW AREA INTO N-CNTRL WY/S-CNTRL AND SERN MT WHERE INTENSIFYING LARGE-SCALE FORCING WILL BECOME CO-LOCATED WITH A ZONE OF WEAK TO MODERATE INSTABILITY. ELSEWHERE...AN ISOLATED SEVERE WEATHER THREAT MAY EXIST BEYOND 23Z...HOWEVER IT APPEARS THAT THE TEMPORAL DURATION OF THIS THREAT WILL BE TOO LIMITED TO WARRANT THE ISSUANCE OF AN ADDITIONAL WW. ..MEAD.. 04/05/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PUB...BOU...CYS...ABQ...RIW...GJT...FGZ...SLC...PIH... 43521113 43560949 42540830 42470568 36600617 36741098 WWWW From Mcd at goshenarc.org Thu Apr 6 03:38:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 05 Apr 2006 23:38:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 060337 SWOMCD SPC MCD 060336 MOZ000-ILZ000-IAZ000-060500- MESOSCALE DISCUSSION 0433 NWS STORM PREDICTION CENTER NORMAN OK 1036 PM CDT WED APR 05 2006 AREAS AFFECTED...E-CNTRL MO NWD INTO CNTRL AND SRN IA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 060336Z - 060500Z ELEVATED TSTM COVERAGE IS EXPECTED TO INCREASE ACROSS DISCUSSION AREA OVERNIGHT. SEVERE HAIL WILL BE POSSIBLE WITH THE MOST INTENSE STORMS AND CONVECTIVE TRENDS WILL BE MONITORED FOR A WW ISSUANCE. AS OF 0320Z...REGIONAL RADAR IMAGERY SHOWED A PERSISTENT CLUSTER OF ELEVATED STORMS FROM WASHINGTON COUNTY NWWD INTO CALLAWAY COUNTY MO WITH NICKEL TO GOLFBALL-SIZED HAIL RECENTLY REPORTED. ANOTHER CLUSTER OF ELEVATED TSTMS HAS PERSISTED FROM NEAR CID SEWD TO E OF UIN. FINALLY...IR SATELLITE DATA SHOW A BAND OF CLOUD ENHANCEMENT FROM THE ONGOING...E-CNTRL MO ACTIVITY NWWD TO NEAR OMA. REGIONAL VWP/PROFILER DATA AND SHORT-TERM MODEL GUIDANCE SUGGEST THAT THIS ACTIVITY IS OCCURRING ALONG AN INTENSIFYING SLY/SWLY LLJ ON THE ERN OR NERN EDGE OF CAP WHICH IS IN PLACE OVER THE CNTRL PLAINS /PER 00Z SOUNDING OBSERVATIONS/. HERE...INCREASING MOISTURE IN THE 850-800 MB LAYER BENEATH STEEP MID-LEVEL LAPSE RATES ARE RESULTING IN AIR MASS DESTABILIZATION FOR ELEVATED PARCELS WITH MUCAPES OF 1000-1500 J/KG. AN INCREASE IN STORM COVERAGE IS ANTICIPATED OVERNIGHT OWING TO FURTHER STRENGTHENING OF LLJ AND RESULTANT FORCING VIA WAA AND ISENTROPIC ASCENT. GIVEN THE MODERATE INSTABILITY AND SHEAR THROUGH THE CLOUD-BEARING LAYER...SEVERE HAIL WILL BE POSSIBLE WITH THE STRONGEST STORMS. ..MEAD.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...DMX...EAX...OAX... 38479132 38539224 40279512 41519592 41969536 42129316 41839182 40539070 39079055 38699088 WWWW From Mcd at goshenarc.org Thu Apr 6 06:22:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 02:22:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 060621 SWOMCD SPC MCD 060620 SDZ000-NEZ000-060745- MESOSCALE DISCUSSION 0434 NWS STORM PREDICTION CENTER NORMAN OK 0120 AM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL/SRN SD AND EXTREME NRN NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 060620Z - 060745Z TSTMS OVER SWRN SD WILL LIKELY EXPAND ESEWD INTO EXTREME NRN NEB AND ACROSS A LARGE PART OF SRN/CNTRL SD EARLY THIS MORNING. STRONGER STORMS WILL PRODUCE LARGE HAIL AND A SEVERE THUNDERSTORM WATCH MAY BE REQUIRED. H5 JET OF 70+ KTS ALONG ERN PERIPHERY OF THE WY UPPER LOW WAS NOSING NWD INTO WRN NEB...PLACING A STRONG DIFFLUENT/DIVERGENT FLOW REGIME ACROSS THE CNTRL/NRN HIGH PLAINS EARLY THIS MORNING. CORRESPONDING SLY LLJ OF AROUND 50 KTS WAS IMPINGING ON AN E-W ORIENTED BAROCLINIC ZONE SITUATED ACROSS THE NE/SD BORDER. RESULTING DEEP UVV WAS ALREADY SUPPORTING TSTMS ACROSS SWRN SD. PRIND THAT TSTMS WILL DEVELOP ESEWD ALONG/N OF THE AFOREMENTIONED BAROCLINIC ZONE INTO EXTREME NRN NEB AND CNTRL/SRN SD THE NEXT FEW HOURS. THOUGH EFFECTIVE VERTICAL SHEAR IS GENERALLY LESS THAN 35 KTS...LAPSE RATES WERE QUITE STEEP. THUS...AS TSTMS DEVELOP...UPDRAFTS WILL BE STRONG WITH LARGE HAIL PRODUCTION QUITE LIKELY. AS THE NUMBER OF STORMS INCREASE...COMPETITION OF UPDRAFTS MAY TEND TO TEMPER THE SEVERITY OF THE STORMS LATER IN THE MORNING. BUT...THERE APPEARS THAT THERE WILL BE A FEW HOURS OF LARGE HAIL POTENTIAL AND A WW MAY BE REQUIRED. ..RACY.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FSD...OAX...ABR...LBF...UNR...CYS... 44870270 44689987 44379712 44039719 42089784 42319911 43020306 WWWW From Mcd at goshenarc.org Thu Apr 6 11:02:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 07:02:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061101 SWOMCD SPC MCD 061101 MOZ000-KSZ000-IAZ000-NEZ000-061300- MESOSCALE DISCUSSION 0435 NWS STORM PREDICTION CENTER NORMAN OK 0601 AM CDT THU APR 06 2006 AREAS AFFECTED...SERN NEB...NERN KS...NWRN MO CONCERNING...OUTLOOK UPGRADE VALID 061101Z - 061300Z AFTER COLLABORATION WITH THE TOP/OAX/EAX WEATHER FORECAST OFFICES... THE STORM PREDICTION CENTER IS EXPECTED TO UPGRADE SERN NEB...NERN KS AND NWRN MO TO A CATEGORICAL HIGH RISK AT 13Z. H5 12-HR HEIGHT FALLS OF 210 METERS WILL SPREAD ENEWD ACROSS THE CNTRL PLAINS THIS AFTN. TSTMS ARE EXPECTED TO DEVELOP BY EARLY AFTN ALONG THE DRYLINE/SFC LOW FROM SCNTRL NEB INTO CNTRL KS AS INHIBITION IS ERODED. STORMS SHOULD QUICKLY ORGANIZE INTO SUPERCELLS GIVEN STRONG VERTICAL SHEAR PROFILES /H5 FLOW OF 105 KTS OVER OKLA...WITH AOA 60 KTS INTO ERN KS/. THE 2-8KM SHEAR VECTORS REMAIN SUFFICIENTLY NORMAL TO THE INITIATING BOUNDARY TO SUPPORT DISCRETE CELLS...THOUGH ACTIVITY WILL TEND TO EVOLVE INTO A MIXED MODE OF LEWPS/BOWS WITH TIME. NONETHELESS...BACKED SELY LOW-LEVEL FLOW E/NE OF THE SFC LOW/WARM FRONT WILL BE FAVORABLE FOR TORNADOES...SOME STRONG...AS THE STORMS MOVE ENEWD AT 30-40 KTS ACROSS NERN KS...SERN NEB AND NWRN MO. VERY LARGE HAIL CAN ALSO BE EXPECTED GIVEN STEEP MID-LEVEL LAPSE RATES AND 2000-2500 J/KG MLCAPE. ..RACY/EVANS.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EAX...OAX...TOP... 38339578 39589716 40779702 40919601 40319468 39399408 38529421 38249500 WWWW From Mcd at goshenarc.org Thu Apr 6 16:04:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 12:04:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061603 SWOMCD SPC MCD 061603 ARZ000-MOZ000-LAZ000-TXZ000-OKZ000-KSZ000-061800- MESOSCALE DISCUSSION 0436 NWS STORM PREDICTION CENTER NORMAN OK 1103 AM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK/SW MO/WRN AR/ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061603Z - 061800Z ...POTENTIAL FOR ISOLD SEVERE STORMS THROUGH EARLY AFTN FROM ECNTRL OK SWD TO PARTS OF ERN TX...AND EWD INTO AR... ELEVATED TSTMS CONTINUE TO INTENSIFY ACROSS ECNTRL OK...WITH LATEST TULSA OK RADAR IMAGERY SUGGESTING INTENSE MID LEVEL CORES. LATEST WV IMAGERY INDICATES AN IMPULSE NOW MOVING ACROSS CNTRL KS/OK...AND THIS IS LIKELY AGITATING THE STORMS. IN ADDITION...LARGE SCALE ASCENT IS BEING AUGMENTED BY DIFFLUENT FLOW ALOFT. 12Z SOUNDING FROM NORMAN OK SHOWED AROUND 1700 J/KG MUCAPE...WITH SLIGHTLY STRONGER CAPE EVIDENT ON THE 12Z SPRINGFIELD MO SOUNDING. SPECIAL 15Z SOUNDING FROM SPRINGFIELD SUGGESTS STORMS ARE ROOTED NEAR 700MB. STORMS ARE FORMING WITHIN AN ENVIRONMENT OF STRONG DEEP LAYER SHEAR /AROUND 40 KT/ AND MODERATE ELEVATED INSTABILITY. STORMS ARE EXPECTED TO CONTINUE DEVELOPING SWD...WITH THE MAIN THREAT FROM LARGE HAIL. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...HGX...ICT...FWD...OUN... 33039395 30769505 30649667 33689707 36159641 37239475 37299338 36099266 33919325 WWWW From Mcd at goshenarc.org Thu Apr 6 16:20:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 12:20:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061619 SWOMCD SPC MCD 061619 INZ000-KYZ000-ILZ000-MOZ000-IAZ000-061715- MESOSCALE DISCUSSION 0437 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 06 2006 AREAS AFFECTED...SERN IA/ERN MO/MUCH OF CENTRAL-SRN IL/FAR SWRN IND/FAR WRN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061619Z - 061715Z ELEVATED STORMS WILL CONTINUE TO DEVELOP INTO THE AFTERNOON FROM SERN IA SEWD THROUGH ERN MO/MUCH OF CENTRAL-SRN IL INTO FAR SWRN IND AND FAR WRN KY. LATE MORNING SURFACE ANALYSIS SHOWED A DEEPENING SURFACE LOW LOCATED OVER ERN NEB...WITH A WARM FRONT EXTENDING SEWD THROUGH SWRN IA/NRN TO ERN MO AROUND STL..AND THEN EWD ACROSS SRN IL INTO FAR SRN IND. A SURFACE TROUGH EXTENDED SWD FROM CENTRAL MO /BOONE COUNTY/ INTO NRN AR. LARGE SCALE ASCENT DOWNSTREAM OF SHORT WAVE TROUGH LOCATED OVER CENTRAL KS/OK WILL SUPPORT ADDITIONAL ELEVATED STORMS TO THE NORTH OF THE WARM FRONT AND EAST OF THE SURFACE TROUGH...AS THIS MID LEVEL IMPULSE TRACKS NEWD TOWARD THE LOWER MO/MID MS VALLEYS TODAY. SPECIAL 15Z SOUNDING AT SGF CONTINUED TO INDICATE A STEEP LAPSE RATE ENVIRONMENT OVER MO...BUT THE AIR MASS REMAINS CAPPED. 15Z RUC SOUNDINGS ACROSS THE DISCUSSION AREA SUGGEST STORMS ARE ROOTED AROUND 850 MB WITH CLOUD LAYER SHEAR SUPPORTIVE OF ELEVATED ROTATING STORMS. WEAK INSTABILITY SHOULD LIMIT THE COVERAGE OF STRONGER CORES. HOWEVER...STEEP LAPSE RATES INDICATED A THREAT FOR ISOLATED HAIL...LOCALLY EXCEEDING SEVERE LEVELS AT TIMES. ..PETERS.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...ILX...LSX...DVN...DMX...EAX... 40639240 41659279 41989165 41799039 40608889 39848761 38408698 36838743 36628864 36728976 37889107 39269164 WWWW From Mcd at goshenarc.org Thu Apr 6 17:14:00 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 13:14:00 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061712 SWOMCD SPC MCD 061712 NEZ000-KSZ000-061915- MESOSCALE DISCUSSION 0438 NWS STORM PREDICTION CENTER NORMAN OK 1212 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH ERN NEB THROUGH MUCH OF CNTRL KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061712Z - 061915Z THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS PORTIONS OF CNTRL NEB SWD THROUGH CNTRL KS BETWEEN 19 AND 21Z. ORGANIZED STORM STRUCTURES APPEAR LIKELY INCLUDING SUPERCELLS AND LINE SEGMENTS. THREATS WILL INCLUDE LARGE HAIL AND A FEW TORNADOES. ISOLATED DAMAGING WIND WILL ALSO BE POSSIBLE. A TORNADO WATCH WILL LIKELY BE NEEDED FOR PORTIONS OF THESE AREAS BY 18Z. EARLY THIS AFTERNOON A SURFACE FRONT EXTENDS FROM A LOW IN E CNTRL NEB SWWD THROUGH W CNTRL KS THEN SWD AS A DRYLINE/PACIFIC FRONT THROUGH WRN OK AND THE ERN PORTION OF WRN TX. WV IMAGERY SHOWS A LOBE OF VORTICITY AND ACCOMPANYING UPPER JET ADVANCING ENEWD THROUGH WRN KS AND WRN NEB. ASCENT AND HEIGHT FALLS ASSOCIATED WITH THIS FEATURE WILL CONTRIBUTE TO SECONDARY CYCLOGENESIS OVER N CNTRL KS THIS AFTERNOON. LATEST SURFACE ANALYSIS ALREADY SHOWS PRESSURE FALLS ACROSS CNTRL THROUGH SWRN KS. AS THE SURFACE LOW DEVELOPS...THE BOUNDARY LAYER FLOW OVER NEB SHOULD BECOME MORE ELY WITH SOME WWD RETREAT OF THE FRONT AND LOW LEVEL MOISTURE. STRONG SURFACE HEATING...ASCENT...AND EWD ADVANCE COLDER AIR ALOFT AND STEEPER LAPSE RATES WILL CONTINUE TO DESTABILIZE THE ATMOSPHERE FROM CNTRL THROUGH ERN NEB SWD THROUGH CNTRL KS WITH MLCAPE FROM 1500 TO 2000 J/KG LIKELY LATER THIS AFTERNOON. MID LEVEL CLOUDS DEVELOPING ACROSS PORTIONS OF WRN AND CNTRL KS ARE PROBABLY INDICATIVE OF THE LEADING EDGE OF ASCENT SPREADING EWD. AS THE ATMOSPHERE CONTINUES TO DESTABILIZE AND HEIGHT FALLS/FORCING FOR ASCENT SPREAD EWD...STORMS SHOULD DEVELOP IN VICINITY OF FRONT/DRYLINE FROM CNTRL NEB SWD THROUGH CNTRL KS AND SUBSEQUENTLY SPREAD NEWD. DEEP LAYER AND LOW LEVEL SHEAR WILL CONTINUE TO INCREASE AS THE UPPER JET ADVANCES EWD AND AS SECONDARY BRANCH OF THE LOW LEVEL JET INTENSIFIES ACROSS KS/ERN NEB IN RESPONSE TO CYCLOGENESIS. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...TOP...ICT...GID...LBF...DDC...GLD... 41229639 39119663 37159726 37339891 39319945 40499975 42000019 42469914 42259744 WWWW From Mcd at goshenarc.org Thu Apr 6 17:52:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 13:52:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061751 SWOMCD SPC MCD 061751 OKZ000-061945- MESOSCALE DISCUSSION 0439 NWS STORM PREDICTION CENTER NORMAN OK 1251 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH PARTS OF NERN OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061751Z - 061945Z N CNTRL THROUGH CNTRL OK ARE BEING MONITORED FOR POSSIBLE THUNDERSTORM INITIATION BETWEEN 18Z AND 19Z. PRIMARY THREATS WILL BE SUPERCELLS WITH LARGE HAIL AND ISOLATED TORNADOES. THIS AREA IS BEING MONITORED FOR A POSSIBLE TORNADO WATCH. EARLY THIS AFTERNOON A SURFACE FRONT EXTENDS FROM CNTRL KS SSWWD THROUGH WRN OK. A DRYLINE EXTENDS FROM NWRN TX NWD THROUGH W CNTRL OK AND INTERSECTS THE FRONT IN S CNTRL KS. STRONG SURFACE HEATING AND STEEP LAPSE RATES ARE PROMOTING DESTABILIZATION WITHIN THE WARM SECTOR WHERE DEWPOINTS ARE IN THE LOWER 60S. LATEST OBJECTIVE ANALYSIS ALREADY SHOW AN AXIS OF MLCAPE ON THE ORDER OF 1500 TO 2000 J/KG ACROSS W CNTRL OK IN ADVANCE OF THE DRYLINE. PRESSURE FALLS INDICATIVE OF STRONG FORCING FOR ASCENT ASSOCIATED WITH ENEWD ADVANCING MID LEVEL JET ARE DEVELOPING ACROSS WRN AND W CNTRL KS. THIS ZONE OF FALLS WILL CONTINUE TO SPREAD EWD WITH SURFACE CYCLOGENESIS EXPECTED ACROSS CNTRL KS NEXT FEW HOURS. AS THE LOW DEEPENS...CONVERGENCE WILL INCREASE AND THE DRYLINE/COLD FRONT WILL SHARPEN. THE INCREASING CONVERGENCE AND FORCING FOR ASCENT MAY BE SUFFICIENT FOR THUNDERSTORM INITIATION THIS AFTERNOON INTO PARTS OF CNTRL OK AS THE CAP WEAKENS. LATEST VISIBLE IMAGERY SHOWS BOUNDARY LAYER CUMULUS INCREASING OVER W CNTRL OK JUST W OF OKC. STRENGTHENING LOW TO MID LEVEL WIND FIELDS AND VERTICAL SHEAR WILL SUPPORT SUPERCELL STRUCTURES WITH ANY STORMS THAT DEVELOP. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...OUN... 35099786 35689789 36379788 36949788 36849577 35919599 35119696 WWWW From Mcd at goshenarc.org Thu Apr 6 18:17:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 14:17:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061816 SWOMCD SPC MCD 061815 TXZ000-OKZ000-061945- MESOSCALE DISCUSSION 0440 NWS STORM PREDICTION CENTER NORMAN OK 0115 PM CDT THU APR 06 2006 AREAS AFFECTED...SW OK THROUGH SW TX CONCERNING...CONVECTIVE TRENDS VALID 061815Z - 061945Z ...DRYLINE BEING MONITORED FOR CONVECTIVE TRENDS ACROSS SW OK THROUGH TX... LATEST VISIBLE SATELLITE IMAGERY SHOWS BLOWING DUST WEST OF THE DRYLINE AND BOUNDARY LAYER CUMULUS EAST. EARLY THIS AFTN...THE DRYLINE EXTENDS FROM JUST EAST OF HBR/FDR/SNK/FST. UPPER/MID LEVEL CIRCULATION IS SEEN ON WV LOOPS NOW APPROACHING TX PANHANDLE. ALTHOUGH MOST OF THE LARGE SCALE FORCING WILL BE FOCUSED NORTH OF THE AREA...STRONG SFC HEATING COMBINED WITH LOW LEVEL ASCENT FOCUSED ON THE DRYLINE/PACIFIC FRONT MAY BE ENOUGH TO INITIATE STORMS THIS AFTN. STEEP LAPSE RATES...COMBINED WITH STRONG DEEP LAYER SHEAR AND INCREASING MOISTURE INTO THE WARM SECTOR WILL FAVOR STRONG/SEVERE STORMS...IF AND WHEN DEVELOPMENT OCCURS. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 34709755 32949716 31199785 30259964 30960080 31370067 32439994 32849982 34149889 34429876 34869833 WWWW From Mcd at goshenarc.org Thu Apr 6 19:03:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 15:03:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 061902 SWOMCD SPC MCD 061902 MNZ000-SDZ000-NDZ000-062100- MESOSCALE DISCUSSION 0441 NWS STORM PREDICTION CENTER NORMAN OK 0202 PM CDT THU APR 06 2006 AREAS AFFECTED...SD/WRN MN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 061902Z - 062100Z ...STRONG AND SEVERE TSTMS WILL CONTINUE ACROSS PORTIONS OF SOUTH DAKOTA NORTH OF WARM FRONT WITH PRIMARILY A THREAT OF LARGE HAIL... MORNING UPPER AIR ANALYSIS AT 850 MB REVEALS BAROCLINIC ZONE ACROSS NRN NEB/SRN SD...AND THIS IS SERVING AS A FOCUS FOR TSTM DEVELOPMENT THIS AFTN. LARGE SCALE ASCENT WILL INCREASE ACROSS THE AREA...SO TSTMS ARE EXPECTED TO CONTINUE THROUGH THE AFTN. LATEST SFC OBSERVATIONAL ANALYSIS SHOWS MUCAPE AROUND 1000-1500 J/KG. STEEP MID LEVEL LAPSE RATES WILL FAVOR STRONG UPDRAFTS...CAPABLE OF LARGE HAIL. IN ADDITION...TRAINING CELLS WILL ALSO POSE A HEAVY RAIN THREAT AS WELL. STORMS MAY HAVE A TENDENCY TO BUILD EWD INTO WRN PORTIONS OF MN LATER THIS AFTN DUE TO INCREASING WAA. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MPX...FGF...FSD...ABR...BIS...UNR... 43819657 43770137 44310263 45640292 46249941 45899568 44269571 WWWW From Mcd at goshenarc.org Thu Apr 6 20:25:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 16:25:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062024 SWOMCD SPC MCD 062024 IAZ000-NEZ000-SDZ000-062230- MESOSCALE DISCUSSION 0442 NWS STORM PREDICTION CENTER NORMAN OK 0324 PM CDT THU APR 06 2006 AREAS AFFECTED...CNTRL THROUGH ERN KS...ERN NEB THROUGH WRN IA CONCERNING...TORNADO WATCH 154... VALID 062024Z - 062230Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY TOWARD EVENING FROM ERN KS INTO ERN NEB. THREAT FOR SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND ISOLATED TORNADOES WILL CONTINUE. ISOLATED DAMAGING WIND IS ALSO POSSIBLE. STORMS ARE EXPECTED TO DEVELOP INTO NERN NEB AND WRN IA AFTER 22Z. A WW MAY BE NEEDED FOR THIS AREA WITHIN THE NEXT HOUR OR TWO. THUNDERSTORMS WILL CONTINUE TO INCREASE IN VICINITY OF THE PACIFIC FRONT ACROSS CNTRL KS AS ASCENT ASSOCIATED WITH A STRONG MID LEVEL JET OVERTAKES THE MOIST AXIS. PRESSURE FALLS HAVE INCREASED OVER CNTRL KS IN RESPONSE TO AGEOSTROPHIC FORCING ASSOCIATED WITH THIS FEATURE...AND LEE CYCLONE DEVELOPMENT IS ALSO UNDERWAY OVER N CNTRL KS. PRIMARY LIMITING FACTOR FOR MORE SIGNIFICANT TORNADOES IN THE SHORT TERM HAS BEEN THE SOMEWHAT MARGINAL LOW LEVEL SHEAR AND RELATIVELY HIGH BOUNDARY LAYER-TEMPERATURE DEWPOINT SPREADS. HOWEVER...THE TORNADO THREAT IS EXPECTED TO INCREASE LATER THIS AFTERNOON AND EVENING. THE LOW LEVEL JET WILL STRENGTHEN FROM ERN KS INTO SERN NEB...AND THIS WILL CONTRIBUTE TO AN INCREASE IN LOW LEVEL SHEAR WITHIN THE PRE-FRONTAL WARM SECTOR. SOME DECREASE IN TEMPERATURE-DEWPOINT SPREADS MAY ALSO OCCUR TOWARD EVENING AS THE BOUNDARY LAYER BEGINS TO COOL. ACTIVITY WILL GRADUALLY DEVELOP NEWD THROUGH ERN AND NERN NEB AS WELL AS WRN IA TOWARD EVENING AS FORCING FOR ASCENT SPREADS NEWD. CONVECTIVE MODE WILL INCLUDE SUPERCELLS AS WELL AS LINES WITH LARGE HAIL...ISOLATED TORNADOES AND DAMAGING WIND POSSIBLE. ..DIAL.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...FSD...OAX...LBF... 41939463 41409479 41239539 41629610 41739734 41809878 42329901 42829747 42609539 WWWW From Mcd at goshenarc.org Thu Apr 6 20:31:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 16:31:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062030 SWOMCD SPC MCD 062029 ARZ000-MOZ000-062200- MESOSCALE DISCUSSION 0443 NWS STORM PREDICTION CENTER NORMAN OK 0329 PM CDT THU APR 06 2006 AREAS AFFECTED...SCNTRL MO/NCNTRL AR CONCERNING...SEVERE THUNDERSTORM WATCH 153... VALID 062029Z - 062200Z THE MAIN THREAT ACROSS WW 153 IS NOW EAST OF A RUE/BPK LINE. ELEVATED TSTMS HAVE MOVED INTO SCNTRL MO AND NCNTRL AR...WITH THE MOST INTENSE STORM NOW PASSING SE OF FLP. POTENTIAL FOR ADDITIONAL SEVERE WEATHER WILL INCREASE OVER THE NEXT 2-4 HOURS...AS STORMS CONTINUE TO DEVELOP ACROSS NE OK AHEAD OF EWD MOVING SFC BOUNDARY...WHICH EXTENDS ACROSS CNTRL OK. ENVIRONMENT ACROSS NW AR/SW MO HAS BEEN TEMPORARILY STABILIZED DUE TO ELEVATED STORMS WHICH OCCURRED EARLIER AND DESTABILIZATION WILL NEED TO OCCUR. SPECIAL 20Z SOUNDING FROM SPRINGFIELD SHOWS MID LEVEL WARMING HAS OCCURRED ROUGHLY IN THE 600-700MB LAYER. MLCAPE VALUES ARE 1500-2000 J/KG WITHIN INSTABILITY AXIS ACROSS CNTRL OK. LAPSE RATES REMAIN STEEP...AND WIND PROFILES REMAIN FAVORABLE FOR ROTATING STORMS. TO EXPRESS THIS INCREASING SEVERE THREAT ACROSS NE OK/NW AR...THE HIGH RISK HAS BEEN EXTENDED INTO THIS AREA AS OF 20Z. FOR THE REMAINDER OF WW 153 HOWEVER...THE POTENTIAL FOR ELEVATED TSTMS IS DIMINISHING...AND THE WATCH WILL LIKELY EXPIRE AS SCHEDULED AT 23Z. A NEW WATCH WILL BE NEEDED WITHIN A FEW HOURS...POSSIBLY INCLUDING ERN PORTIONS OF TORNADO WATCH 155 AND POINTS FARTHER EAST. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF... 35479151 35079341 35809321 37319268 37639151 37169144 35999136 WWWW From Mcd at goshenarc.org Thu Apr 6 21:22:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 17:22:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062121 SWOMCD SPC MCD 062121 ARZ000-MOZ000-OKZ000-KSZ000-062245- MESOSCALE DISCUSSION 0444 NWS STORM PREDICTION CENTER NORMAN OK 0421 PM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK/WRN AR CONCERNING...TORNADO WATCH 155... VALID 062121Z - 062245Z ...WATCH WILL NEED TO BE ISSUED SHORTLY FOR PORTIONS OF WRN AND NRN AR... TSTMS DEVELOPING MOVING INTO SEBASTIAN CO ARE SFC BASED...AND WILL HAVE AN INCREASING THREAT FOR ROTATING CELLS/TORNADOES. THUS...A TORNADO WATCH WILL NEED TO BE CONSIDERED FOR AR AND MO SOON. FARTHER WEST...TORNADO HAS BEEN REPORTED WITH SUPERCELL ACROSS OSAGE CO AND VAD WIND DATA FROM TULSA CONTINUES TO BE VERY FAVORABLE FOR SUPERCELLS WITH TORNADOES AND LARGE HAIL. ..TAYLOR.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...ICT...OUN... 34149385 34419573 35529671 36869665 37109581 37019491 36399162 34609218 WWWW From Mcd at goshenarc.org Thu Apr 6 21:54:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 17:54:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 062153 SWOMCD SPC MCD 062153 MOZ000-IAZ000-OKZ000-KSZ000-NEZ000-062330- MESOSCALE DISCUSSION 0445 NWS STORM PREDICTION CENTER NORMAN OK 0453 PM CDT THU APR 06 2006 AREAS AFFECTED...FAR ERN KS INTO WRN AND CNTRL MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 062153Z - 062330Z POTENTIAL FOR SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES IS EXPECTED TO SPREAD E OF WW 154 BY 23Z AND A NEW TORNADO WATCH WILL BE REQUIRED. AS OF 21Z...MESOANALYSIS INDICATED A RAPIDLY DEEPENING SURFACE LOW OVER S-CNTRL NEB WITH ATTENDANT DRYLINE SURGING ENEWD THROUGH S-CNTRL INTO ERN KS. INTENSE LARGE-SCALE FORCING FOR ASCENT AHEAD OF MID-LEVEL TROUGH AND ASSOCIATED 90-100 KT JET STREAK ARE CONTRIBUTING INCREASING STORM COVERAGE AND INTENSITY FROM MARION COUNTY KS SEWD INTO OSAGE COUNTY OK. STEEP LAPSE RATES COUPLED WITH DIABATIC HEATING AND MODEST BOUNDARY-LAYER DEWPOINTS HAVE CONTRIBUTED TO A MODERATELY UNSTABLE AIR MASS LATE THIS AFTERNOON E OF ONGOING STORMS WITH MLCAPES OF 1000-2000 J/KG. REGIONAL PROFILERS AND VWPS INDICATE DESCENDING MID AND HIGH-LEVEL JET ACROSS INSTABILITY AXIS WITH 55-65 KTS OF DEEP-LAYER SHEAR. MOREOVER...TRENDS IN NEODESHA KS PROFILER SHOW THAT LOW-LEVEL SHEAR HAS STEADILY INCREASED THROUGH THE AFTERNOON. THIS TREND WILL CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON INTO THIS EVENING EWD INTO WRN AND CNTRL MO...SUGGESTING A THREAT FOR LONG-LIVED SUPERCELLS CAPABLE OF A COUPLE STRONG TORNADOES. ..MEAD.. 04/06/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...DMX...EAX...TSA...OAX...TOP...ICT... 39979556 40569467 40589317 39699257 37519211 36699275 36509328 36539433 36669483 WWWW From Mcd at goshenarc.org Fri Apr 7 00:08:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:08:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070007 SWOMCD SPC MCD 070007 TXZ000-OKZ000-070130- MESOSCALE DISCUSSION 0446 NWS STORM PREDICTION CENTER NORMAN OK 0707 PM CDT THU APR 06 2006 AREAS AFFECTED...NCNTRL THROUGH SCNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 156... VALID 070007Z - 070130Z LATEST MESOANALYSIS SHOWS PACIFIC COLD FRONT/DRYLINE EXTENDING FROM LUD/SEP/DRT. AHEAD OF THIS BOUNDARY...SVR TSTM HAS DEVELOPED OVER BURNET COUNTY...WITH A STRONG MID LEVEL CORE AND WITHIN A STRONGLY SHEARED ENVIRONMENT. VISIBLE SATELLITE IMAGERY SHOWS CUMULUS FIELD EXTENDING SWD TO DRT. MODERATE INSTABILITY AXIS SHOWS MLCAPE RANGING FROM 1500-2000 J/KG WITHIN AIRMASS WHERE DEWPOINTS ARE STILL IN THE 60S. WATER VAPOR IMAGERY SUGGESTS STRONGEST FORCING IS FOCUSED FARTHER NORTH...SO ADDITIONAL DEVELOPMENT IS EXPECTED TO BE ISOLD. HOWEVER...ANY SUSTAINED STORMS THAT FORM WILL LIKELY BECOME SEVERE WITH THE MAIN THREAT OF LARGE HAIL OR DAMAGING WINDS. ..TAYLOR.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...HGX...FWD...OUN...EWX...SJT... 30199683 30379848 31379861 33979708 33789457 30709622 WWWW From Mcd at goshenarc.org Fri Apr 7 00:13:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:13:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070012 SWOMCD SPC MCD 070012 IAZ000-MOZ000-KSZ000-NEZ000-070115- MESOSCALE DISCUSSION 0447 NWS STORM PREDICTION CENTER NORMAN OK 0712 PM CDT THU APR 06 2006 AREAS AFFECTED...WRN IA / NWRN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 070012Z - 070115Z THREAT OF LARGE HAIL...LOCALLY DAMAGING WINDS AND PERHAPS A FEW TORNADOES IS EXPECTED TO DEVELOP E OF WW 154 PRIOR 01-02Z. A NEW WW WILL LIKELY BE REQUIRED. AS OF 2355Z...REGIONAL RADAR IMAGERY INDICATED WIDESPREAD TSTMS ONGOING OVER PORTIONS OF ERN NEB...TO THE E OF OCCLUDING SURFACE LOW OVER CNTRL NEB. WITHIN THIS BROADER CONVECTIVE SHIELD...A MESOSCALE CIRCULATION WAS OBSERVED LIFTING NEWD THROUGH SEWARD...LANCASTER...SALINE...JEFFERSON AND GAGE COUNTIES. OMA AND TOP RADAR DATA INDICATE THE PRESENCE OF SMALLER-SCALE SUPERCELL STRUCTURES WITHIN N-S BAND ALONG ERN EDGE OF THIS CIRCULATION AS FAR S AS NEMAHA AND POTTAWATOMIE COUNTIES IN NERN KS. PRESENCE OF DEEP-LAYER FORCING FOR ASCENT IN DIFLUENT REGION OF UPPER SYNOPTIC SYSTEM SHOULD SUPPORT CONTINUED DEVELOPMENT NEWD INTO WRN IA/NWRN MO THROUGH THE EVENING. DESPITE LARGELY MERIDIONAL MID AND HIGH-LEVEL WIND FIELDS...BACKED SURFACE WINDS E/SE OF THE SURFACE LOW ARE RESULTING IN VERTICAL SHEAR PROFILES SUPPORTIVE OF SUPERCELLS WITH AN ANTICIPATED CONTINUING THREAT OF LARGE HAIL...LOCALLY DAMAGING WIND GUSTS AND PERHAPS A FEW TORNADOES. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP... 42119626 42249580 42129513 41199411 39519384 39119413 38949469 39219512 WWWW From Mcd at goshenarc.org Fri Apr 7 00:55:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 20:55:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070054 SWOMCD SPC MCD 070053 ARZ000-MOZ000-OKZ000-TXZ000-070230- MESOSCALE DISCUSSION 0448 NWS STORM PREDICTION CENTER NORMAN OK 0753 PM CDT THU APR 06 2006 AREAS AFFECTED...ERN OK CONCERNING...TORNADO WATCH 155...157... VALID 070053Z - 070230Z ...HIGH POTENTIAL FOR TORNADOES AND LARGE HAIL WITH DISCRETE SUPERCELLS NOW MOVING ACROSS ERN OK.... LATEST RADAR IMAGERY SHOWS SEVERAL SUPERCELL TSTMS EXTENDING FROM FAR SE KS TO SE OK. ENVIRONMENTAL PARAMETERS ARE VERY FAVORABLE FOR STORM ROTATION...WITH 0-1 SRH NEAR 400 M2/S2. HASKELL OK PROFILER AND VAD DATA FROM BOTH TULSA AND FORT SMITH SHOW VERY IMPRESSIVE DIRECTION/SPEED SHEAR WITH 50 KT OBSERVED NEAR 1 KM. LAMONT AND PURCELL PROFILER DATA ALSO SHOW 100KT DOWN TO 3KM...INDICATING THE EXTREMELY STRONG WINDS...ASSOCIATED WITH EJECTING JET STREAK. SEVERAL OF THESE STORMS HAVE ALREADY PRODUCED BRIEF TORNADOES...INCLUDING A RECENT REPORT OF A TORNADO WEST OF EUFAULA DAM IN HASKELL CO JUST BEFORE 730PM. STORM SIGNATURES DO INDICATE THAT STORMS ARE FEELING THE EFFECTS OF THE EXTREME SHEAR. HOWEVER...THE STORMS /BY MAINTAINING SOME SPACE BETWEEN CELLS/ ARE NOT DESTRUCTIVELY INTERFERING...WHICH DOES INCREASE THE POTENTIAL FOR TORNADOES. BEST POTENTIAL APPEARS TO BE ACROSS SE OK INTO WCNTRL AR. AIRMASS IS SLIGHTLY MORE STABLE ACROSS NW AR...BUT MOISTURE IS RAPIDLY RETURNING IN A SLIGHTLY ELEVATED FASHION. STRENGTH OF SHEAR SUGGESTS SEVERE THREAT WILL SPREAD INTO PORTIONS OF WW 157 /INTO NRN AND WRN AR/ THROUGH LATER THIS EVENING. ..TAYLOR.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SGF...SHV...TSA...FWD...OUN... 33789476 33839619 35609549 36979517 36929403 35429388 34569387 WWWW From Mcd at goshenarc.org Fri Apr 7 01:30:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 21:30:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070129 SWOMCD SPC MCD 070129 KSZ000-MOZ000-IAZ000-NEZ000-SDZ000-070300- MESOSCALE DISCUSSION 0449 NWS STORM PREDICTION CENTER NORMAN OK 0829 PM CDT THU APR 06 2006 AREAS AFFECTED...N-CNTRL AND ERN NEB / ERN KS CONCERNING...SEVERE THUNDERSTORM WATCH 154...158... VALID 070129Z - 070300Z SEVERE WEATHER THREAT IS EXPECTED TO SHIFT E OF WW 154 BY 02Z...THEREFORE THIS WW WILL BE ALLOWED TO EXPIRE AT THAT TIME. ELSEWHERE...OVERALL SEVERE WEATHER POTENTIAL APPEARS TO BE DIMINISHING ACROSS N-CNTRL AND NERN NEB...SUGGESTING WW 158 COULD POSSIBLY BE CANCELLED EARLY. AS OF 0120Z...REGIONAL RADAR IMAGERY SHOWED A LINE OF STRONG TO POTENTIALLY SEVERE TSTMS FROM BURT COUNTY NEB SWD ALONG THE MO RIVER INTO BROWN AND JACKSON COUNTIES IN NERN KS. DESPITE LARGELY MERIDIONAL INDIVIDUAL CELL MOTIONS...OVERALL LINE MOVEMENT IS MORE EWD WHICH SHOULD TAKE THIS DEVELOPMENT INTO WW 160 BY 02Z. FARTHER TO THE N...WIDESPREAD CONVECTION HAS RESULTED IN CONSIDERABLE STABILIZATION OF AIR MASS WITH MOST VIGOROUS DEVELOPMENT OCCURRING ALONG NRN FRINGE OF PRECIPITATION SHIELD FROM GREGORY AND CHARLES MIX COUNTIES EWD TO YANKTON COUNTY IN SD. THESE STRONGER STORMS WILL REMAIN CAPABLE OF PRIMARILY MARGINALLY SEVERE HAIL. LITTLE ADDITIONAL DESTABILIZATION IS ANTICIPATED TONIGHT OWING TO THE LOSS OF DAYTIME HEATING AND AFOREMENTIONED WIDESPREAD COLD POOL DEVELOPMENT. THEREFORE...SHOULD CURRENT CONVECTIVE TRENDS CONTINUE...PORTIONS OF WW 158 COULD BE CANCELLED EARLY /SPECIFICALLY FROM SW TO NE/. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...FSD...OAX...TOP...ICT...GID...LBF...UNR... 37049626 43110057 43019659 40039540 37049503 WWWW From Mcd at goshenarc.org Fri Apr 7 02:28:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 22:28:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070227 SWOMCD SPC MCD 070227 TXZ000-OKZ000-070330- MESOSCALE DISCUSSION 0450 NWS STORM PREDICTION CENTER NORMAN OK 0927 PM CDT THU APR 06 2006 AREAS AFFECTED...NERN INTO CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 156... VALID 070227Z - 070330Z SOME THREAT OF MARGINALLY SEVERE HAIL MAY PERSIST FOR THE NEXT COUPLE OF HOURS ACROSS PARTS OF CNTRL TX. AN ADDITIONAL WW IS NOT ANTICIPATED. AS OF 02Z...MESOANALYSIS INDICATED PACIFIC COLD FRONT FROM E OF ADM SWD THROUGH THE METROPLEX TO W OF TPL. STRONG TO SEVERE TSTMS WHICH HAVE PERSISTED FOR THE PAST COUPLE OF HOURS FROM NEAR ACT TO AUS HAVE WEAKENED CONSIDERABLY OVER THE PAST HALF HOUR...PRESUMABLY OWING TO STRENGTHENING CAP ACROSS MODERATELY UNSTABLE...PRE-FRONTAL AIRMASS. CURRENT WATER VAPOR IMAGERY SUGGESTS THAT THE SRN FRINGE OF LARGE-SCALE FORCING ASSOCIATED WITH CNTRL PLAINS UPPER LOW IS RAPIDLY SHIFTING NE OF THE REGION. THUS...DESPITE THE PRESENCE OF THE MODERATE INSTABILITY AND STRONG SHEAR PROFILES...IT APPEARS THAT A MORE ORGANIZED SEVERE THREAT WILL CONTINUE TO DIMINISH. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...HGX...FWD...OUN...EWX... 34049586 33969479 33409445 30869560 30239713 30259778 30949808 33999639 WWWW From Mcd at goshenarc.org Fri Apr 7 02:52:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 22:52:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070251 SWOMCD SPC MCD 070251 MOZ000-IAZ000-MNZ000-KSZ000-NEZ000-SDZ000-070445- MESOSCALE DISCUSSION 0451 NWS STORM PREDICTION CENTER NORMAN OK 0951 PM CDT THU APR 06 2006 AREAS AFFECTED...NRN MO/WRN IA...SWRN MN AND SERN SD CONCERNING...TORNADO WATCH 160... VALID 070251Z - 070445Z THREAT FOR TORNADOES APPEARS TO HAVE DIMINISHED AS BOUNDARY LAYER CONTINUES TO DECOUPLE. HOWEVER...THREAT FOR SVR HAIL WILL STILL EXIST FOR SEVERAL MORE HRS OVER MUCH OF WW 160. REDEVELOPMENT OF ISOLATED SVR STORMS WILL REMAIN POSSIBLE ALONG WRN PORTIONS OF WW 160 /WRN IA/ OVER THE NEXT FEW HRS...AS MAIN MID LEVEL FORCING INTERACTS WITH REMAINING MODERATE INSTABILITY /MUCAPES AROUND 1500 J/KG/. MAIN THREAT WITH THIS ACTIVITY WILL BE SVR HAIL...ALTHOUGH AN ISOLATED TORNADO WILL BE POSSIBLE THROUGH AROUND MIDNIGHT OVER SWRN IA WHERE AIRMASS HAS NOT BEEN CONVECTIVELY STABILIZED YET. FARTHER NORTH...MORE MARGINAL INSTABILITY /MUCAPES LESS THAN 1000 J/KG/ ACROSS FAR NWRN IA/SERN SD AND SWRN MN/ WILL SUPPORT MORE LIMITED SVR HAIL POTENTIAL. THUS A NEW WW IS NOT ANTICIPATED NORTH OF WW 160. FARTHER SOUTH AN ORGANIZED CONVECTIVE LINE OVER CENTRAL MO...ON THE NOSE OF THE MID LEVEL JET...WILL CONTINUE TO PUSH THROUGH SERN PORTION OF WW 160 /CENTRAL MO/ AND INTO NERN MO OVER THE NEXT FEW HRS. GIVEN WANING INSTABILITY AND DEEPENING STABLE LAYER IN THE LOWEST FEW THOUSAND FEET...A SVR WIND THREAT IS NOT ANTICIPATED TO BE ORGANIZED ENOUGH TO WARRANT A NEW WW OVER NERN MO /EAST OF WW 160/. ..CROSBIE.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...MPX...DMX...EAX...FSD...OAX...TOP... 44149680 43939777 43319714 42299637 41309594 39759527 39109505 38919373 39009273 39979196 41719231 43609452 WWWW From Mcd at goshenarc.org Fri Apr 7 03:23:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 06 Apr 2006 23:23:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 070322 SWOMCD SPC MCD 070321 ARZ000-MOZ000-OKZ000-KSZ000-070445- MESOSCALE DISCUSSION 0452 NWS STORM PREDICTION CENTER NORMAN OK 1021 PM CDT THU APR 06 2006 AREAS AFFECTED...SWRN MO / NW AND N-CNTRL AR CONCERNING...TORNADO WATCH 157...159... VALID 070321Z - 070445Z THROUGH 0430Z...THE GREATEST SEVERE WEATHER THREAT WILL EXIST FROM HRO TO W OF RUE EWD TO E OF UNO SWD TO LIT. ISOLATED TORNADOES...LOCALLY DAMAGING WINDS AND LARGE HAIL REMAIN POSSIBLE WITH THE MOST INTENSE STORMS. AS OF 03Z...REGIONAL RADAR IMAGERY INDICATED A BROKEN LINE OF STRONG TO SEVERE STORMS FROM BOONE COUNTY AR SWWD TO SCOTT COUNTY AR MOVING 245/40-50 KTS. EMBEDDED CELLS OVER BOONE AND LOGAN/YELL COUNTIES INDICATE THE PRESENCE OF MESOCYCLONES WITH REFLECTIVITY DATA SUGGESTING HP SUPERCELL CHARACTERISTICS. LOCAL PROFILERS AND VWPS INDICATE THAT INFLOW AIR MASS ACROSS THE NWRN QUARTER OF AR IS STRONGLY SHEARED WITH 0-1 KM SRH OF 400-500 M2/S2 AND DEEP LAYER SHEAR OF 65-75 KTS. PRIMARY UNCERTAINTY IS WHETHER THESE STORMS ARE TRULY SURFACE-BASED OR SLIGHTLY ELEVATED ABOVE A NEAR SURFACE INVERSION. RELATIVELY LIGHT SURFACE WINDS...GROUND CLUSTER SIGNATURE OBSERVED ON LIT 88D AND RUC FORECAST SOUNDINGS DO SUGGEST THAT THIS ACTIVITY MAY BE ELEVATED TO SOME DEGREE WHICH MAY TEND TO LIMIT A GREATER TORNADO THREAT. HOWEVER...GIVEN THE STRONG SHEAR AND UNCERTAINTY REGARDING THE DEPTH OF THIS INVERSION...POTENTIAL FOR ISOLATED TORNADOES STILL EXISTS...IN ADDITION TO LARGE HAIL AND LOCALLY DAMAGING WINDS. FARTHER TO THE N IN MO...COMPARATIVELY WEAKER INSTABILITY APPEARS TO BE LIMITING STORM INTENSITY. SHOULD CURRENT TRENDS CONTINUE...AN ADDITIONAL WW MAY NOT BE NEEDED ACROSS E-CNTRL AND PARTS OF SERN MO. HOWEVER...A NEW TORNADO WATCH MAY BECOME NECESSARY WITHIN THE NEXT COUPLE OF HOURS OVER NERN AR PERHAPS INTO FAR SERN MO. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...LZK...SGF...EAX...TSA... 38849490 38819167 34639137 34719462 WWWW From Mcd at goshenarc.org Fri Apr 7 14:09:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 10:09:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071408 SWOMCD SPC MCD 071407 KYZ000-TNZ000-INZ000-ALZ000-ILZ000-MSZ000-MOZ000-ARZ000-071600- MESOSCALE DISCUSSION 0453 NWS STORM PREDICTION CENTER NORMAN OK 0907 AM CDT FRI APR 07 2006 AREAS AFFECTED...PARTS OF ERN AR...WRN TN AND MIDDLE TN...NRN MS...SERN MO...WRN KY AND SRN IL...SWRN IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071407Z - 071600Z PARTS OF LOWER AND MIDDLE MS VALLEY AND TN VALLEY ARE BEING MONITORED FOR SURFACE BASED THUNDERSTORM DEVELOPMENT. THREAT FOR SUPERCELLS CAPABLE OF PRODUCING VERY LARGE HAIL AND A FEW STRONG TORNADOES IS EXPECTED TO INCREASE LATER THIS MORNING AND INTO THE AFTERNOON. A TORNADO WATCH WILL LIKELY BE NEEDED FOR PARTS OF THIS AREA WITHIN THE NEXT 1 TO 2 HOURS. EARLY THIS MORNING A LONE ELEVATED STORM CONTINUES ACROSS WRN TN. THIS STORM IS DEVELOPING WITHIN A ZONE OF ASCENT AND LOW LEVEL WARM ADVECTION ALONG A SWLY LOW LEVEL JET. VISIBLE IMAGERY SHOWS OTHER CLOUDS ON THE NRN EDGE OF THE THICKER STRATUS BEGINNING TO TAKE ON A MORE CONVECTIVE CHARACTER. LOW LEVEL MOISTURE WITH DEWPOINTS IN THE LOW TO MID 60S HAS SPREAD THROUGH THE LOWER MS VALLEY AND WRN PARTS OF THE TN VALLEY. MORNING RAOB DATA SHOW STEEPER MID LEVEL LAPSE RATES UPSTREAM THAT WILL LIKELY ADVECT EWD DURING THE DAY. THIS WILL CONTRIBUTE TO DESTABILIZATION AS LOW CLOUDS CONTINUE TO MIX OUT. MORNING ACARS AND RAOB DATA ALSO INDICATE A WEAK CAP REMAINING AND SUGGEST ONLY MODEST BOUNDARY LAYER WARMING IS NEEDED FOR STORMS TO BECOME SURFACE BASED. WV IMAGERY SHOWS A PRONOUNCED DRYSLOT MOVING INTO PORTIONS OF THE LOWER MS VALLEY BUT WITH AN AXIS OF DEEPER MOISTURE FROM MS NWD THROUGH ERN AR...WRN TN...SERN MO AND WRN KY. ADDITIONAL STORMS WILL LIKELY DEVELOP LATER THIS MORNING AND INTO THE AFTERNOON WITHIN THIS AXIS OF DEEPER MOISTURE AS THE CAP WEAKENS AND AS A VORT MAX PIVOTS SEWD TOWARD THE LOWER MS VALLEY. THE NATURE OF THE LOW LEVEL AND DEEP LAYER VERTICAL SHEAR PROFILES WILL SUPPORT SUPERCELL STRUCTURES WITH LARGE HAIL AND A FEW STRONG TORNADOES POSSIBLE. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...HUN...PAH...MEG...LZK... 36838661 35278727 34128880 34349176 37778961 38158759 WWWW From Mcd at goshenarc.org Fri Apr 7 15:48:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 11:48:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071547 SWOMCD SPC MCD 071547 ALZ000-MSZ000-ARZ000-LAZ000-071745- MESOSCALE DISCUSSION 0454 NWS STORM PREDICTION CENTER NORMAN OK 1047 AM CDT FRI APR 07 2006 AREAS AFFECTED...ERN AR...NERN LA...CNTRL AND NRN MS...CNTRL AND NRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071547Z - 071745Z THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER PORTIONS OF THE LOWER MS VALLEY AND SPREAD EWD DURING THE DAY. SUPERCELLS WITH VERY LARGE HAIL AND A FEW STRONG TORNADOES WILL BE THE PRIMARY THREATS. A WW WILL LIKELY BE NEEDED FOR MUCH OF THIS AREA WITHIN THE HOUR. THIS MORNING AN AXIS OF RICHER LOW LEVEL MOISTURE WITH DEWPOINTS IN THE LOW TO MID 60S HAS SPREAD NEWD THROUGH THE LOWER MS VALLEY. THE LATEST VISIBLE IMAGERY CONTINUES TO SHOW EXTENSIVE STRATUS. HOWEVER...MIXING IS INCREASING AROUND THE EDGES OF THIS STRATUS DECK WITH CLOUDS BECOMING MORE CONVECTIVE IN NATURE ACROSS ERN AR. THE SPECIAL 14Z RAOB FROM JACKSON MS SHOWED SOME COOLING HAS OCCURRED IN THE 850-700 MB LAYER WITH LITTLE CAP REMAINING. THIS SUGGEST ONLY A MODEST AMOUNT OF SURFACE HEATING IS NEEDED WITHIN THE MOIST AXIS TO PROMOTE SURFACE BASED THUNDERSTORM INITIATION. THE ATMOSPHERE WILL CONTINUE TO DESTABILIZE AS STEEP MID LEVEL LAPSE RATES ADVECT EWD ABOVE THE WARMING BOUNDARY LAYER. STORMS ARE EXPECTED TO DEVELOP INITIALLY OVER SERN AR AND NRN MS THEN SPREAD EWD. A 30-40 KT SWLY LOW LEVEL JET WILL PERSIST DOWNSTREAM FROM SEWD ADVANCING UPPER TROUGH. THIS FEATURE AND A STRONG WSWLY MID LEVEL JET WILL CONTRIBUTE TO FAVORABLE LOW LEVEL AND DEEP LAYER SHEAR FOR SUPERCELLS. GIVEN THE NATURE OF THE THERMODYNAMIC AND KINEMATIC PROFILES AND EXPECTED DISCRETE MODES...A FEW STRONG TORNADOES WILL BE POSSIBLE. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN...MEG...JAN...LZK...SHV... 33269277 34719142 34958843 34788574 33298596 32039145 WWWW From Mcd at goshenarc.org Fri Apr 7 17:25:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 13:25:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071724 SWOMCD SPC MCD 071723 OHZ000-INZ000-ILZ000-071930- MESOSCALE DISCUSSION 0455 NWS STORM PREDICTION CENTER NORMAN OK 1223 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL IL...CNTRL IND...THROUGH W CNTRL OH CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071723Z - 071930Z PORTIONS OF THE OH VALLEY ARE BEING MONITORED FOR THUNDERSTORM INITIATION. ONCE STORMS DEVELOP...SUPERCELLS AND LINES APPEAR LIKELY WITH LARGE HAIL AND DAMAGING WIND THE PRIMARY THREATS. AREA IS BEING MONITORED FOR A POSSIBLE WW. EARLY THIS AFTERNOON LOW LEVEL MOISTURE WITH DEWPOINTS IN THE UPPER 50S TO LOWER 60S CONTINUE TO ADVECT NEWD TOWARD THE OH VALLEY. HOWEVER...WITH THE LOW LEVEL FLOW EXPECTED TO REMAIN MORE WLY...THE RICHER MOISTURE IS EXPECTED TO REMAIN S OF THIS AREA. THE MOIST BOUNDARY LAYER SOMEWHAT SHALLOW...AND TREND HAS BEEN FOR THE SURFACE DEWPOINTS TO MIX DOWN. NEVERTHELESS...SURFACE HEATING AND STEEP MID LEVEL LAPSE RATES WILL CONTRIBUTE TO MLCAPE FROM 1000 TO 1500 J/KG. AN INCREASE IN CUMULUS CONTINUES TO BE OBSERVED WITHIN THE WARM SECTOR S OF A SWD MOVING COLD FRONT THAT CURRENTLY EXTENDS FROM NRN OH WWD THROUGH NRN IND AND NRN IL. POTENTIAL FOR STORMS TO DEVELOP ALONG AND AHEAD OF THE FRONT WILL INCREASE THROUGH THIS AFTERNOON AS THE BOUNDARY LAYER CONTINUES TO WARM. LARGELY WLY UNIDIRECTIONAL BUT STRONG SHEAR PROFILES WILL SUPPORT ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS...BUT SOME STORMS MAY ALSO EVOLVE INTO LINES OR CLUSTERS. WITH THE PRIMARY LOW LEVEL JET EXPECTED TO REMAIN S OF THIS REGION...LOW LEVEL SHEAR SHOULD REMAIN MODEST. THIS IN CONJUNCTION WITH THE DRYER BOUNDARY LAYER SUGGEST THE PRIMARY THREATS SHOULD REMAIN LIMITED TO LARGE HAIL AND DAMAGING WIND. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX...LSX... 39358373 38678827 38828993 39798993 40518892 40818728 41178564 40478343 WWWW From Mcd at goshenarc.org Fri Apr 7 18:36:54 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 14:36:54 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071835 SWOMCD SPC MCD 071835 WVZ000-OHZ000-VAZ000-NCZ000-TNZ000-KYZ000-INZ000-071930- MESOSCALE DISCUSSION 0456 NWS STORM PREDICTION CENTER NORMAN OK 0135 PM CDT FRI APR 07 2006 AREAS AFFECTED...MUCH OF OH/ERN KY/WV/FAR SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 071835Z - 071930Z WW WILL BE ISSUED SOON FOR MUCH OF CENTRAL/SRN OH SWD ACROSS ERN KY/WRN WV AND FAR SWRN VA. AIR MASS ACROSS THE DISCUSSION AREA WILL CONTINUE TO DESTABILIZE /MLCAPE AROUND 1000 J/KG NOW INTO FAR SWRN OH/ERN KY/TN/ AS LOW-LEVEL MOISTURE RETURNS ENEWD THROUGH THE MID-UPPER OH/TN VALLEYS. THIS COMBINED WITH STRONG SURFACE HEATING AND STEEPENING MID LEVEL LAPSE RATES PER REGIONAL 18Z SOUNDINGS WILL RESULT IN MODERATE INSTABILITY ACROSS THE REST OF THIS AREA. SWLY MID-LEVEL WINDS WILL CONTINUE TO STRENGTHEN THIS AFTERNOON AS 60-80 JET TRANSLATES ENE ACROSS THE OH VALLEY. DEEP LAYER SHEAR ALREADY OVER 50 KT WILL SUPPORT ORGANIZED STRONG TO SEVERE STORMS. ALTHOUGH WIND FIELDS ARE GENERALLY UNI-DIRECTIONAL WITH LITTLE LOW-LEVEL DIRECTIONAL SHEAR...STRONG LOW-LEVEL SPEED SHEAR AS INDICATED BY THE 18Z PIT SOUNDING SUGGESTS THE POTENTIAL FOR TORNADOES. A FEW SHOWERS/ISOLATED THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS ERN KY INTO WV...WITH UPSTREAM ACTIVITY ACROSS IND AND CENTRAL KY EXPECTED TO MOVE INTO OH/ERN KY BY 20Z. ..PETERS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...PBZ...RLX...CLE...MRX...JKL...ILN...LMK...IWX...OHX... 40938473 41228324 41048060 38738051 36528169 36288400 36408477 37418494 WWWW From Mcd at goshenarc.org Fri Apr 7 19:25:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 15:25:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 071923 SWOMCD SPC MCD 071922 KYZ000-ALZ000-TNZ000-INZ000-ILZ000-MSZ000-MOZ000-ARZ000-LAZ000-072115- MESOSCALE DISCUSSION 0457 NWS STORM PREDICTION CENTER NORMAN OK 0222 PM CDT FRI APR 07 2006 AREAS AFFECTED...NERN LA...ERN AR...WRN AND MIDDLE TN...CNTRL AND NRN MS AND AL...SERN MO...SRN IL...SRN IND AND WRN THROUGH CNTRL KY CONCERNING...TORNADO WATCH 162...163... VALID 071922Z - 072115Z THREAT FOR A FEW STRONG LONG TRACK TORNADOES IS EXPECTED TO PERSIST WITH STORMS MOVING THROUGH WRN AND MIDDLE TN INTO WRN AND CNTRL KY NEXT FEW HOURS. ISOLATED TORNADOES REMAIN POSSIBLE FROM SRN IL INTO SRN IND. OTHER STORMS ARE EXPECTED TO DEVELOP FARTHER S ACROSS PARTS OF SERN AR...NRN LA INTO MS AND AL THIS AFTERNOON AND EVENING. THESE STORMS WILL POSE A THREAT FOR A FEW STRONG TORNADOES AND VERY LARGE HAIL ONCE THEY DEVELOP. THE ATMOSPHERE REMAINS MODERATELY UNSTABLE OVER THE LOWER MS VALLEY AND PARTS OF THE SERN U.S. WITH MLCAPE FROM 1500 TO 2000 J/KG FROM NERN LA...SERN AR INTO CNTRL AND NRN MS AND NRN AL. THE 18Z RAOB FROM JACKSON STILL SHOWED SOME CONVECTIVE INHIBITION IN THE 850 MB-700 MB LAYER. WARMING AND MIXING WITHIN THE BOUNDARY LAYER AND HEIGHT FALLS ASSOCIATED WITH SEWD ADVANCING UPSTREAM VORT MAX SUGGEST THE POTENTIAL FOR INITIATION WILL BECOME INCREASINGLY LIKELY WITHIN ZONE OF MODEST WARM ADVECTION OVER THE LOWER MS VALLEY. THE STRONG MID LEVEL JET ASSOCIATED WITH THE UPSTREAM SHORTWAVE TROUGH WILL SHIFT SLOWLY SEWD AND REMAIN IN A FAVORABLE POSITION RELATIVE TO THE LOW LEVEL JET FOR VERTICAL SHEAR CONDUCIVE FOR SUPERCELLS WITH STRONG LOW LEVEL MESOCYCLONES. NEW STORMS THAT DEVELOP WILL LIKELY REMAIN DISCRETE FOR SEVERAL HOURS. KINEMATIC AND THERMODYNAMIC PROFILES WILL CONTINUE TO SUPPORT A THREAT FOR VERY LARGE HAIL AND STRONG TORNADOES. TORNADOES CONTINUE TO BE CONFIRMED WITH SUPERCELLS MOVING THROUGH WRN AND MIDDLE TN AS WELL AS PORTIONS OF WRN AND CNTRL KY. THIS ACTIVITY WILL LIKELY PERSIST AND SHIFT ENEWD NEXT SEVERAL HOURS. ..DIAL.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...BMX...HUN...PAH...MEG...JAN...LSX...LZK...SHV... 32878673 31849259 35109139 38058958 37828555 WWWW From Mcd at goshenarc.org Fri Apr 7 20:59:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 16:59:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072056 SWOMCD SPC MCD 072056 INZ000-KYZ000-ILZ000-MOZ000-072230- MESOSCALE DISCUSSION 0458 NWS STORM PREDICTION CENTER NORMAN OK 0356 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL IL...CNTRL IND CONCERNING...TORNADO WATCH 164... VALID 072056Z - 072230Z GREATEST TORNADIC THREAT SHOULD BE CONFINED TO THE FAR SRN PORTION OF WW164. ADDITIONAL TSTMS SHOULD CONTINUE TO DEVELOP ALONG SWD MOVING COLD FRONT ACROSS NRN PORTION OF WW164. LARGE HAIL WILL BE THE MAIN THREAT WITH ALL STORMS. SEVERAL CLUSTERS OF MULTICELLS AND SUPERCELLS TSTMS HAVE DEVELOPED IN A MODERATELY UNSTABLE AIRMASS WITH MLCAPES OF 1000 TO 2000 J/KG AND STRONG MID/UPPER-LEVEL SPEED SHEAR. STEEP MID-LAPSE LEVEL RATES AS EVIDENCED BY REGIONAL 18Z RAOBS WILL CONTINUE TO SUPPORT LARGE HAIL...SOME OF WHICH WILL BE SIGNIFICANT GIVEN THE DEGREE OF MID-LEVEL COOLING THAT HAS OCCURRED. LOW-LEVEL WIND FIELDS ARE SUPPORTIVE OF TORNADIC STORMS ALONG THE SRN PERIPHERY OF WW164 AND FURTHER S WHERE NEAR-SURFACE BACKING EXISTS. FURTHER N...THE IND VAD PROFILER SHOWS A UNIDIRECTIONAL WSW LOW-LEVEL SIGNATURE WITH ONLY MODEST SPEED SHEAR. ADDITIONAL CONVECTIVE DEVELOPMENT WILL LIKELY CONTINUE ALONG THE SWD-MOVING COLD FRONT IN VICINITY OF DEC TO MIE AT 20Z. THE STEEP LAPSE RATES ALOFT WILL SUPPORT LARGE HAIL...HOWEVER WEAK AND UNIDIRECTIONAL LOW-LEVEL WIND FIELDS AS EVIDENCED BY ILX AND LSX VAD PROFILERS SUPPORT A DIMINISHING TORNADIC THREAT ACROSS CNTRL IL. ..GRAMS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IND...PAH...ILX...LSX... 40128970 40298819 40368555 40178493 39328494 38928505 38728543 38798670 38608821 38578965 38799022 39578988  From Mcd at goshenarc.org Fri Apr 7 21:01:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 17:01:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072057 SWOMCD SPC MCD 072057 VAZ000-WVZ000-MDZ000-PAZ000-OHZ000-NCZ000-TNZ000-KYZ000-SCZ000-GAZ000-INZ000-072230- MESOSCALE DISCUSSION 0459 NWS STORM PREDICTION CENTER NORMAN OK 0357 PM CDT FRI APR 07 2006 AREAS AFFECTED...CENTRAL AND SRN OH/ERN KY/ERN TN/WRN WV/FAR WRN VA/FAR WRN NC CONCERNING...TORNADO WATCH 165... VALID 072057Z - 072230Z PARAMETERS REMAIN FAVORABLE FOR SUPERCELLS PRODUCING TORNADOES... LARGE HAIL AND DAMAGING WINDS...ESPECIALLY ACROSS THE WRN/SRN PARTS OF WW 165. NUMEROUS THUNDERSTORMS CONTINUE TO DEVELOP/SPREAD ENEWD INTO WRN OH AND ERN KY WHERE THE AIR MASS REMAINED MODERATELY UNSTABLE. MODERATE INSTABILITY EXTENDED SWD INTO ERN TN WITH STRONG/SEVERE STORMS OVER MIDDLE TN EXPECTED TO MOVE INTO SRN PART OF WW 165 DURING THE NEXT FEW HOURS. AREA WSR-88D VADS INDICATED UNI- DIRECTIONAL WIND PROFILES WITH STRONG DEEP LAYER SHEAR SUPPORTING A CONTINUED POTENTIAL FOR SPLITTING SUPERCELLS. STRONGEST LOW-LEVEL SHEAR WAS LOCATED ACROSS THE SRN PART OF WW 165 WHERE THE TORNADO THREAT WILL BE THE GREATEST. FARTHER NE ACROSS CENTRAL/ERN OH...STRONG SURFACE HEATING HAS RESULTED IN DOWNWARD MIXING OF DRY AIR AND AT LEAST 30 DEGREE SURFACE DEWPOINT DEPRESSIONS. STORMS MOVING INTO THIS ENVIRONMENT MAY HAVE A GREATER POTENTIAL FOR DAMAGING WINDS. FARTHER EAST ACROSS CENTRAL/ERN WV INTO NRN VA/WRN MD...30-50 KT OF DEEP LAYER SHEAR WILL SUPPORT A FEW ORGANIZED STORMS. AIR MASS HAS BEEN SLOW TO DESTABILIZE WITH WEAK INSTABILITY EXPECTED TO LIMIT SEVERE THREAT EAST OF WW 165...AT LEAST FOR THE NEXT 1-2 HOURS. ..PETERS.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...PBZ...RLX...CLE...GSP...MRX...JKL...FFC...ILN...LMK...IWX...OHX...IND... 35128555 36788510 40648484 40648157 39808066 39417788 38577818 36878108 36428171 34948315  From Mcd at goshenarc.org Fri Apr 7 21:55:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 17:55:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072153 SWOMCD SPC MCD 072153 LAZ000-ARZ000-TXZ000-072300- MESOSCALE DISCUSSION 0460 NWS STORM PREDICTION CENTER NORMAN OK 0453 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN LA INTO PORTIONS OF ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 072153Z - 072300Z POTENTIAL FOR ISOLATED SEVERE STORMS WILL EXIST THROUGH THE EVENING. CONVECTIVE TRENDS ARE BEING MONITORED FOR A POSSIBLE WW ISSUANCE. VISIBLE AND WATER VAPOR SATELLITE DATA SUGGEST THAT A SEWD MOVING GRAVITY WAVE COUPLED WITH INCREASED LARGE-SCALE FORCING AHEAD OF VORTICITY MAXIMUM PIVOTING SEWD ACROSS NWRN TX HAVE CONTRIBUTED TO BACKBUILDING TSTM DEVELOPMENT THIS AFTERNOON INTO S-CNTRL AR AND N-CNTRL AR. ADDITIONAL SWWD DEVELOPMENT WILL BE POSSIBLE THIS EVENING AS THE FORCING FOR ASCENT CONTINUES TO INCREASE AHEAD OF AFOREMENTIONED VORTICITY MAXIMUM. AMBIENT PRE-FRONTAL AIR MASS REMAINS MODERATELY UNSTABLE LATE THIS AFTERNOON WITH MLCAPES OF 1000-2000 J/KG...AND WHEN COUPLED WITH STRONG UNIDIRECTIONAL WIND PROFILES...POTENTIAL EXISTS FOR SPLITTING SUPERCELLS CAPABLE OF LARGE HAIL...LOCALLY DAMAGING WINDS AND PERHAPS A COUPLE OF TORNADOES. CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED...AND SHOULD IT BECOME MORE APPARENT SIGNIFICANT TSTM DEVELOPMENT WILL BECOME ESTABLISHED W OF WW 163 AN ADDITIONAL WW MAY BE REQUIRED. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...SHV...HGX...FWD... 33469340 33289303 32149291 31509284 30759375 30309476 30629552 31379583 32259527 WWWW From Mcd at goshenarc.org Fri Apr 7 22:14:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 18:14:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072212 SWOMCD SPC MCD 072212 ALZ000-TNZ000-MSZ000-ARZ000-LAZ000-072345- MESOSCALE DISCUSSION 0461 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT FRI APR 07 2006 AREAS AFFECTED...SERN AR / NERN LA / NRN AND CNTRL MS / NRN AND CNTRL AL CONCERNING...TORNADO WATCH 163... VALID 072212Z - 072345Z THROUGH 00Z...THE GREATEST POTENTIAL FOR TORNADOES /SOME OF THEM SIGNIFICANT/ IS EXPECTED IN A SW-NE CORRIDOR FROM SE OF GLH TO NEAR TUP TO NE MSL. SW-NE ORIENTED BAND OF TSTMS CONTINUE TO BECOME BETTER ORGANIZED EARLY THIS EVENING FROM THE ARKLAMS NEWD ACROSS NRN MS WITH SEVERAL STORM SPLITS...SUGGESTING UNIDIRECTIONAL VERTICAL SHEAR PROFILES. THIS NOTION IS CONFIRMED BY CURRENT OKOLONA MS PROFILER DATA WHICH EXHIBIT RELATIVELY STRONG VERTICAL SPEED SHEAR WITH AROUND 60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 100-150 M2/S2. 21Z JAN SOUNDING SHOWED THE PRESENCE OF STEEP MID-LEVEL LAPSE RATES ATOP A LOW-LEVEL MEAN MIXING RATIO OF 10-11 G/KG...WHICH WERE CONTRIBUTING TO MLCAPES OF 1000-1500 J/KG. THIS SOUNDING ALSO EXHIBITED A MODERATELY HIGH LCL /1800 M/ OWING TO BOUNDARY-LAYER TEMPERATURE-DEWPOINTS SPREADS OF AROUND 25 F. DESPITE THE MODEST LOW-LEVEL SHEAR AND LCL HEIGHTS...POTENTIAL WILL EXIST FOR TORNADOES WITH ALL RIGHT MOVING SUPERCELLS ACROSS WW 163 AREA. COOLING/MOISTENING OF BOUNDARY-LAYER COUPLED WITH INCREASING LOW-LEVEL SHEAR AFTER 00Z...SUGGEST THAT THE POTENTIAL FORT A FEW SIGNIFICANT TORNADOES MAY INCREASE AT THIS TIME. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MOB...MEG...JAN...LZK...LCH...SHV... 34599268 35768601 32518609 31269275 WWWW From Mcd at goshenarc.org Fri Apr 7 22:40:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 18:40:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 072238 SWOMCD SPC MCD 072238 VAZ000-NCZ000-WVZ000-080015- MESOSCALE DISCUSSION 0462 NWS STORM PREDICTION CENTER NORMAN OK 0538 PM CDT FRI APR 07 2006 AREAS AFFECTED...CNTRL VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 072238Z - 080015Z POTENTIAL FOR LOCALLY DAMAGING WINDS IS EXPECTED TO DEVELOP E OF WW 166 BY 23Z. SHOULD ONGOING STORMS MAINTAIN THEIR INTENSITY...A WW MAY BE REQUIRED. TRENDS IN REGIONAL RADAR DATA SUGGEST THAT A COLD POOL MAY BE ORGANIZING WITH ONGOING LINE OF TSTMS EXTENDING FROM NE OF SSU TO W OF BLF. DOWNSTREAM AIR MASS OVER CNTRL VA REMAINS QUITE WARM EARLY THIS EVENING WITH TEMPERATURES IN THE LOW TO MID 80S. ASSOCIATED STEEP LOW-LEVEL LAPSE RATES COUPLED WITH RELATIVELY DRY SUB-CLOUD CONDITIONS /I.E. TEMPERATURE-DEWPOINT SPREADS OF 30-40 DEGREES F/ SUGGEST THAT THIS COLD POOL MAY BE MAINTAINED E OF WW 166 WITH THE POTENTIAL FOR DAMAGING WINDS. PRIMARY UNCERTAINTY IS THE DURATION OF THIS THREAT OWING TO THE FACT THAT BOUNDARY-LAYER WILL BEGIN TO COOL OVER THE NEXT COUPLE OF HOURS WITH A RESULTANT WEAKENING OF LOW-LEVEL LAPSE RATES. CURRENT THINKING IS THAT THIS THREAT WILL REMAIN ISOLATED PRIOR TO AIR MASS STABILIZING. HOWEVER...IF IT APPEARS THAT A MORE ORGANIZED THREAT OF DAMAGING WINDS WILL DEVELOP E OF WW AREA...A WW MAY BE REQUIRED. ..MEAD.. 04/07/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RAH...RNK... 38577933 38817877 38597776 37477788 36677825 36537882 36697958 WWWW From Mcd at goshenarc.org Sat Apr 8 02:22:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 22:22:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080221 SWOMCD SPC MCD 080221 VAZ000-NCZ000-WVZ000-080315- MESOSCALE DISCUSSION 0463 NWS STORM PREDICTION CENTER NORMAN OK 0921 PM CDT FRI APR 07 2006 AREAS AFFECTED...ERN KY CONCERNING...TORNADO WATCH 165... VALID 080221Z - 080315Z POTENTIAL FOR ISOLATED DAMAGING WINDS AND SEVERE HAIL MAY PERSIST BEYOND 03Z. HOWEVER...GIVEN THE ANTICIPATED LIMITED AREAL COVERAGE OF THIS THREAT...AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. AS OF 0205Z...REGIONAL RADAR IMAGERY SHOWED A PRE-FRONTAL CONVECTIVE LINE FROM LAWRENCE AND CABELL COUNTIES IN WRN WV SWWD TO WARREN AND SIMPSON COUNTIES IN S-CNTRL KY MOVING SEWD AT 30-40 KTS. RUC OBJECTIVE FIELDS SUGGEST THAT THE STRONGEST INSTABILITY EXISTS TO THE W FROM WRN TN SWD INTO MS AND AL WITH AIR MASS ONLY MARGINALLY UNSTABLE ACROSS ERN KY...TO THE N OF ONGOING STORMS OVER ERN TN. CURRENT JKL VWP INDICATES THAT AMBIENT ENVIRONMENT REMAINS STRONGLY SHEARED WITH 50 KT WSWLY WINDS AT .5 KM INCREASING TO 70 KTS AT 5 KM. THEREFORE...POTENTIAL WILL EXIST FOR LOCALLY DAMAGING WIND GUSTS AND MARGINALLY SEVERE HAIL WITH THE MOST INTENSE STORMS AS THEY MOVE THROUGH NARROW INSTABILITY AXIS. THIS THREAT AREA APPEARS TO BE QUITE LIMITED SPATIALLY AND AN ADDITIONAL WW IS NOT ANTICIPATED ATTM. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RAH...RNK... 38577933 38817877 38597776 37477788 36677825 36537882 36697958 WWWW From Mcd at goshenarc.org Sat Apr 8 03:18:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 23:18:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080317 SWOMCD SPC MCD 080316 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-LAZ000-080445- MESOSCALE DISCUSSION 0464 NWS STORM PREDICTION CENTER NORMAN OK 1016 PM CDT FRI APR 07 2006 AREAS AFFECTED...NERN LA / NRN AND CNTRL MS / NRN AND CNTRL AL CONCERNING...TORNADO WATCH 169... VALID 080316Z - 080445Z POTENTIAL FOR ISOLATED TORNADOES IN ADDITION TO LARGE HAIL AND DAMAGING WINDS WILL CONTINUE ACROSS NRN AND CNTRL PARTS OF WW AREA THROUGH 04-05Z. IT APPEARS THAT THE GREATEST TORNADO THREAT WILL EXIST FROM JUST SW OF MSL EWD THROUGH HSV...EVENTUALLY INTO FAR NERN AL. FARTHER TO THE W...A CONVECTIVE LINE IS BECOMING PROGRESSIVELY MORE SW-NE ORIENTED OVER THE MS DELTA SWWD INTO N-CNTRL LA...SUGGESTING AN INCREASE IN DAMAGING WIND POTENTIAL FROM GLH TO GWO AND EVENTUALLY SWD TO I-20 OVER W-CNTRL MS. AS OF 03Z...REGIONAL RADAR IMAGERY SHOWED A SW-NE ORIENTED CONVECTIVE SHIELD FROM N-CNTRL LA ACROSS NRN MS...NWRN AL INTO MIDDLE AND ERN TN. SEVERAL SUPERCELLS ARE EMBEDDED WITHIN THIS LARGER COMPLEX...THE MOST INTENSE OF WHICH WAS LOCATED OVER LAWRENCE AND MORGAN COUNTIES IN N-CNTRL AL. KINEMATIC ENVIRONMENT /AS SAMPLED BY BHM VWP/ REMAINS STRONGLY SHEARED OWING TO 50-60 KT SWLY WINDS AT 1 KM WITH 0-1 KM SRH OF 350-400 M2/S2. 00Z BHM OBSERVED AND RUC FORECAST SOUNDINGS DO SUGGEST THAT INFLOW AIR MASS MAY BE SLIGHTLY CAPPED WITH MLCAPES OF 1000-1500 J/KG...THOUGH ONGOING INTENSE UPDRAFTS APPEAR TO BE SUCCESSFULLY OVERCOMING ANY CIN. EXTRAPOLATION OF CURRENT LAWRENCE/MORGAN COUNTY SUPERCELL TAKES IT VERY CLOSE TO HSV BY 330Z...AND TO NEAR THE AL/GA STATE LINE BY 430-05Z. FARTHER TO THE W...CONVECTION IS BECOMING MORE N-S ORIENTED FROM TALLAHATCHIE AND LEFLORE COUNTIES IN NWRN MS SWWD TO WEST CARROLL PARISH IN NERN MS. SHOULD THIS TREND CONTINUE...THIS CONVECTION WILL BECOME INCREASINGLY NORMAL TO 50-70 KT MID-LEVEL WIND FIELDS...SUGGESTING THE POTENTIAL FOR BOW OR LEWP ECHO EVOLUTION AND A RESULTANT INCREASING THREAT OF DAMAGING WINDS. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MOB...MEG...JAN...LIX...LZK...LCH...SHV... 33469206 35608530 32858543 30759199 WWWW From Mcd at goshenarc.org Sat Apr 8 03:56:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 07 Apr 2006 23:56:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080355 SWOMCD SPC MCD 080355 LAZ000-ARZ000-TXZ000-080530- MESOSCALE DISCUSSION 0465 NWS STORM PREDICTION CENTER NORMAN OK 1055 PM CDT FRI APR 07 2006 AREAS AFFECTED...FAR ERN TX INTO WRN AND CNTRL LA CONCERNING...TORNADO WATCH 167... VALID 080355Z - 080530Z THROUGH 06Z...POTENTIAL FOR MAINLY DAMAGING WINDS WILL EXIST ACROSS CNTRL AND SRN PORTIONS OF WW AREA. A STRONGLY FORCED CONVECTIVE LINE HAS RAPIDLY EVOLVED OVER THE PAST HALF HOUR ALONG COLD FRONT FROM S-CNTRL AR SWWD INTO SERN TX /SE OF LFK/. CURRENT SURFACE OBSERVATIONS INDICATE THAT PRE-FRONTAL AIR MASS ACROSS LA REMAINS QUITE MOIST WITH DEWPOINTS IN THE MID TO UPPER 60S. MOREOVER...WINNFIELD LA PROFILER SHOWS THAT AMBIENT KINEMATIC ENVIRONMENT IS STRONGLY SHEARED WITH 50-60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 200-300 M2/S2. GIVEN THE PROMINENT LINEAR CONVECTIVE MODE ALONG FRONT...IT APPEARS THAT DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT AS STORMS CONTINUE SEWD AT 30-35 KTS. HOWEVER...THE STRONG LOW-LEVEL SHEAR DOES SUGGEST SOME POTENTIAL FOR EMBEDDED SUPERCELLS OR LEWP STRUCTURES CAPABLE OF AN ISOLATED TORNADO. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LZK...LCH...SHV...HGX... 32979447 33599173 30589174 29959457 WWWW From Mcd at goshenarc.org Sat Apr 8 04:06:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:06:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080405 SWOMCD SPC MCD 080405 KYZ000-TNZ000-INZ000-ALZ000-MSZ000-ILZ000-MOZ000-ARZ000-080600- MESOSCALE DISCUSSION 0466 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN AND MIDDLE TN / WRN AND CNTRL KY / FAR NRN MS CONCERNING...TORNADO WATCH 170... VALID 080405Z - 080600Z LATEST DATA SHOW COMPLEX SURFACE LOW BECOMING BETTER ORGANIZED ATTM OVER THE MO BOOTHEEL. COLD FRONT TRAILING SSW ACROSS ERN AR IS INTENSIFYING IN RESPONSE TO SEWD ACCELERATION AND AMPLIFICATION OF WRN AR UPPER VORT. SEVERAL BOUNDARIES EXTEND GENERALLY ENE FROM THE LOW...WITH THE MOST SIGNIFICANT OF THESE FOR SEVERE PURPOSES NOW NEARLY STATIONARY OVER EXTREME SRN KY. CONTINUED E/SE MOTION OF AR VORT AND ASSOCIATED MID LEVEL COOLING/ASCENT SUGGEST THAT TSTMS MAY INCREASE IN COVERAGE DURING THE NEXT SEVERAL HOURS ALONG THE BOUNDARY IN FAR SRN KY/NW TN. OTHERS MAY ALSO FORM SOMEWHAT LATER SWD ALONG COLD FRONT INTO WRN TN. AREA VWP DATA SHOW AMPLE DEEP SHEAR IN PLACE TO SUPPORT SUPERCELLS AND OTHER MODES OF SUSTAINED STORMS. THE PROFILES SHOULD REMAIN STRONG THROUGH EARLY SATURDAY. HOWEVER...AT LOWER LEVELS...THE OBSERVED DATA AS WELL AS MODEL FORECAST WINDS SHOW EVIDENCE OF CONVECTIVE MODIFICATION AND BACK-VEER PATTERNS WITH HEIGHT. THESE TENDENCIES SHOULD INCREASE WITH TIME AND SUGGEST THAT THE THREAT FOR TORNADOES WILL CONTINUE TO DIMINISH IN WW 170...ESPECIALLY IN SW TN AND NW MS. NEVERTHELESS...WITH APPROACH OF UPPER VORT...A THREAT FOR HAIL AND POSSIBLY DAMAGING WIND LIKELY WILL PERSIST INTO EARLY SATURDAY. ..CORFIDI.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG... 36469030 35229040 33999025 34728802 35748515 37078497 38268533 WWWW From Mcd at goshenarc.org Sat Apr 8 04:11:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:11:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080407 SWOMCD SPC MCD 080406 VAZ000-WVZ000-080500- MESOSCALE DISCUSSION 0467 NWS STORM PREDICTION CENTER NORMAN OK 1106 PM CDT FRI APR 07 2006 AREAS AFFECTED...SOUTHERN WV/SOUTHWEST VA CONCERNING...SEVERE THUNDERSTORM WATCH 166...168... VALID 080406Z - 080500Z PRIMARY SHORT TERM SEVERE THREAT CONTINUES MAINLY ACROSS THE FAR SOUTHERN PORTIONS OF SEVERE WATCHES 166/168 ACROSS SOUTHWEST VA. OTHERWISE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. STRONGEST STORMS ACROSS SEVERE WATCHES 166/168 ARE OCCURRING ACROSS SOUTHWEST VA IN AREAS SOUTH/SOUTHWEST OF BLACKSBURG AND ROANOKE. THIS ACTIVITY IS FOCUSED ALONG/SOUTH OF CONVECTIVE REINFORCED BOUNDARY...WITH AN UNSTABLE SOUTHWESTLY FEED STILL IMPINGING ON THIS BOUNDARY. SIMILAR TO CURRENT TRENDS...PRIMARY SEVERE THREAT WILL REMAIN FOCUSED ACROSS FAR SOUTHERN VA OVER THE NEXT HOUR OR SO. OTHERWISE...SEVERE THREAT WILL CONTINUE TO DIMINISH REMAINDER OF THE NIGHT...AND SEVERE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AT/BY SCHEDULED 05Z EXPIRATIONS ACCORDINGLY. ..GUYER.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK...RLX...MRX... 37658164 38037971 37387842 36707865 36637983 36748121 37048190 WWWW From Mcd at goshenarc.org Sat Apr 8 04:12:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:12:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080355 SWOMCD SPC MCD 080355 LAZ000-ARZ000-TXZ000-080530- MESOSCALE DISCUSSION 0465 NWS STORM PREDICTION CENTER NORMAN OK 1055 PM CDT FRI APR 07 2006 AREAS AFFECTED...FAR ERN TX INTO WRN AND CNTRL LA CONCERNING...TORNADO WATCH 167... VALID 080355Z - 080530Z THROUGH 06Z...POTENTIAL FOR MAINLY DAMAGING WINDS WILL EXIST ACROSS CNTRL AND SRN PORTIONS OF WW AREA. A STRONGLY FORCED CONVECTIVE LINE HAS RAPIDLY EVOLVED OVER THE PAST HALF HOUR ALONG COLD FRONT FROM S-CNTRL AR SWWD INTO SERN TX /SE OF LFK/. CURRENT SURFACE OBSERVATIONS INDICATE THAT PRE-FRONTAL AIR MASS ACROSS LA REMAINS QUITE MOIST WITH DEWPOINTS IN THE MID TO UPPER 60S. MOREOVER...WINNFIELD LA PROFILER SHOWS THAT AMBIENT KINEMATIC ENVIRONMENT IS STRONGLY SHEARED WITH 50-60 KTS OF DEEP-LAYER SHEAR AND 0-1 KM SRH OF 200-300 M2/S2. GIVEN THE PROMINENT LINEAR CONVECTIVE MODE ALONG FRONT...IT APPEARS THAT DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT AS STORMS CONTINUE SEWD AT 30-35 KTS. HOWEVER...THE STRONG LOW-LEVEL SHEAR DOES SUGGEST SOME POTENTIAL FOR EMBEDDED SUPERCELLS OR LEWP STRUCTURES CAPABLE OF AN ISOLATED TORNADO. ..MEAD.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LZK...LCH...SHV...HGX... 32979447 33599173 30589174 29959457  From Mcd at goshenarc.org Sat Apr 8 04:24:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:24:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080405 SWOMCD SPC MCD 080405 KYZ000-TNZ000-INZ000-ALZ000-MSZ000-ILZ000-MOZ000-ARZ000-080600- MESOSCALE DISCUSSION 0466 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 07 2006 AREAS AFFECTED...WRN AND MIDDLE TN / WRN AND CNTRL KY / FAR NRN MS CONCERNING...TORNADO WATCH 170... VALID 080405Z - 080600Z LATEST DATA SHOW COMPLEX SURFACE LOW BECOMING BETTER ORGANIZED ATTM OVER THE MO BOOTHEEL. COLD FRONT TRAILING SSW ACROSS ERN AR IS INTENSIFYING IN RESPONSE TO SEWD ACCELERATION AND AMPLIFICATION OF WRN AR UPPER VORT. SEVERAL BOUNDARIES EXTEND GENERALLY ENE FROM THE LOW...WITH THE MOST SIGNIFICANT OF THESE FOR SEVERE PURPOSES NOW NEARLY STATIONARY OVER EXTREME SRN KY. CONTINUED E/SE MOTION OF AR VORT AND ASSOCIATED MID LEVEL COOLING/ASCENT SUGGEST THAT TSTMS MAY INCREASE IN COVERAGE DURING THE NEXT SEVERAL HOURS ALONG THE BOUNDARY IN FAR SRN KY/NW TN. OTHERS MAY ALSO FORM SOMEWHAT LATER SWD ALONG COLD FRONT INTO WRN TN. AREA VWP DATA SHOW AMPLE DEEP SHEAR IN PLACE TO SUPPORT SUPERCELLS AND OTHER MODES OF SUSTAINED STORMS. THE PROFILES SHOULD REMAIN STRONG THROUGH EARLY SATURDAY. HOWEVER...AT LOWER LEVELS...THE OBSERVED DATA AS WELL AS MODEL FORECAST WINDS SHOW EVIDENCE OF CONVECTIVE MODIFICATION AND BACK-VEER PATTERNS WITH HEIGHT. THESE TENDENCIES SHOULD INCREASE WITH TIME AND SUGGEST THAT THE THREAT FOR TORNADOES WILL CONTINUE TO DIMINISH IN WW 170...ESPECIALLY IN SW TN AND NW MS. NEVERTHELESS...WITH APPROACH OF UPPER VORT...A THREAT FOR HAIL AND POSSIBLY DAMAGING WIND LIKELY WILL PERSIST INTO EARLY SATURDAY. ..CORFIDI.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...JKL...LMK...OHX...HUN...PAH...MEG... 36469030 35229040 33999025 34728802 35748515 37078497 38268533  From Mcd at goshenarc.org Sat Apr 8 04:24:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 00:24:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080407 SWOMCD SPC MCD 080406 VAZ000-WVZ000-080500- MESOSCALE DISCUSSION 0467 NWS STORM PREDICTION CENTER NORMAN OK 1106 PM CDT FRI APR 07 2006 AREAS AFFECTED...SOUTHERN WV/SOUTHWEST VA CONCERNING...SEVERE THUNDERSTORM WATCH 166...168... VALID 080406Z - 080500Z PRIMARY SHORT TERM SEVERE THREAT CONTINUES MAINLY ACROSS THE FAR SOUTHERN PORTIONS OF SEVERE WATCHES 166/168 ACROSS SOUTHWEST VA. OTHERWISE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. STRONGEST STORMS ACROSS SEVERE WATCHES 166/168 ARE OCCURRING ACROSS SOUTHWEST VA IN AREAS SOUTH/SOUTHWEST OF BLACKSBURG AND ROANOKE. THIS ACTIVITY IS FOCUSED ALONG/SOUTH OF CONVECTIVE REINFORCED BOUNDARY...WITH AN UNSTABLE SOUTHWESTLY FEED STILL IMPINGING ON THIS BOUNDARY. SIMILAR TO CURRENT TRENDS...PRIMARY SEVERE THREAT WILL REMAIN FOCUSED ACROSS FAR SOUTHERN VA OVER THE NEXT HOUR OR SO. OTHERWISE...SEVERE THREAT WILL CONTINUE TO DIMINISH REMAINDER OF THE NIGHT...AND SEVERE WATCHES 166/168 WILL BE ALLOWED TO EXPIRE AT/BY SCHEDULED 05Z EXPIRATIONS ACCORDINGLY. ..GUYER.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK...RLX...MRX... 37658164 38037971 37387842 36707865 36637983 36748121 37048190  From Mcd at goshenarc.org Sat Apr 8 07:32:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 03:32:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080731 SWOMCD SPC MCD 080730 ALZ000-GAZ000-MSZ000-LAZ000-080900- MESOSCALE DISCUSSION 0468 NWS STORM PREDICTION CENTER NORMAN OK 0230 AM CDT SAT APR 08 2006 AREAS AFFECTED...NERN LA/CENTRAL MS/CENTRAL AL CONCERNING...TORNADO WATCH 169... VALID 080730Z - 080900Z SEVERE STORMS CONTINUE MOVING EWD ACROSS SRN PORTIONS OF WW 169. THREAT MAY SPILL S OF WW WITH TIME...POSSIBLY REQUIRING NEW WW ACROSS SRN AL AND PERHAPS SERN MS. VIGOROUS CONVECTION CONTINUES ALONG AND AHEAD OF COLD FRONT NOW CROSSING THE MID MS VALLEY/LA. RAOB FROM JACKSON MS AT 06Z REVEALS CAPE/SHEAR COMBINATION VERY FAVORABLE FOR SEVERE STORMS. THOUGH CAPPING REMAINS AN ISSUE WITH SWD EXTENT -- AS CONFIRMED BY LIMIT TO SWD EXTENSION OF STORMS ALONG FRONT...IT APPEARS THAT SEVERE THREAT MAY SPILL SWD OUT OF WW --- PARTICULARLY ACROSS SRN AL S OF WW. FURTHER...STORMS MAY NOT COMPLETELY VACATE WW ACROSS PORTIONS OF CENTRAL MS/CENTRAL AL BY 09Z -- WHEN WW IS SCHEDULED TO EXPIRE. THEREFORE...NEW WW COULD BE NEEDED FROM SRN PORTIONS OF WW 169 SWD INTO PARTS OF SRN MS/SRN AL. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MOB...JAN...LIX...LCH... 31189195 32759033 34578547 32038519 30619030 30789198 WWWW From Mcd at goshenarc.org Sat Apr 8 07:47:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 03:47:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 080746 SWOMCD SPC MCD 080745 NCZ000-SCZ000-GAZ000-080845- MESOSCALE DISCUSSION 0469 NWS STORM PREDICTION CENTER NORMAN OK 0245 AM CDT SAT APR 08 2006 AREAS AFFECTED...NRN GA/WRN SC CONCERNING...TORNADO WATCH 171... VALID 080745Z - 080845Z STORMS CONTINUE MOVING EWD ACROSS WW...THOUGH MOST VIGOROUS STORMS WILL MOVE SEWD INTO WW 172. WW WILL LIKELY BE ALLOWED TO EXPIRE AT 09Z. LATEST RADAR IMAGERY SHOWS STRONGEST CONVECTION -- NOW OVER FAR SERN PORTIONS OF WW -- MOVING SEWD INTO WW 172. MEANWHILE...STORMS FURTHER N INTO NRN GA HAVE SHOWN A SLOW WEAKENING TREND WITH TIME. THIS SEEMS TO CONFIRM LATEST OBJECTIVE ANALYSES...WHICH INDICATE ONLY MARGINAL INSTABILITY AT BEST OVER NRN GA. WITH EVEN LESS UNSTABLE AIRMASS INDICATED INTO THE WRN CAROLINAS...EXPECT STORMS TO CONTINUE WEAKENING AS THEY MOVE EWD. THEREFORE...NEW WW IS NOT ANTICIPATED. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 34238460 34958375 35228230 34248298 33998406 WWWW From Mcd at goshenarc.org Sat Apr 8 11:44:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 07:44:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081142 SWOMCD SPC MCD 081142 GAZ000-ALZ000-081315- MESOSCALE DISCUSSION 0470 NWS STORM PREDICTION CENTER NORMAN OK 0642 AM CDT SAT APR 08 2006 AREAS AFFECTED...CENTRAL GA CONCERNING...TORNADO WATCH 172... VALID 081142Z - 081315Z BROKEN LINE OF THUNDERSTORMS CONTINUE DRIFTING SWD ACROSS THE SRN HALF OF WW WHILE WEAKENING WITH TIME. LIMITED SEVERE THREAT CONTINUES. LATEST RADAR IMAGERY INDICATES A BROKEN LINE OF STORMS -- ALONG THE LEADING EDGE OF A SEWD-MOVING OUTFLOW BOUNDARY -- MOVING ACROSS CENTRAL GA ATTM. THOUGH DEEP-LAYER SHEAR REMAINS SUFFICIENT FOR SEVERE STORMS...MODEL SOUNDINGS AND LATEST OBJECTIVE ANALYSES INDICATE LIMITED INSTABILITY S OF ONGOING STORMS. THOUGH A LIMITED THREAT FOR SEVERE WEATHER -- MAINLY IN THE FORM OF HAIL -- MAY PERSIST FOR THE NEXT HOUR OR TWO...OVERALL CONVECTIVE TRENDS SHOULD REMAIN DOWNWARD. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...FFC...BMX... 32428525 32898399 33478256 32468258 32118523 WWWW From Mcd at goshenarc.org Sat Apr 8 12:31:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 08:31:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081230 SWOMCD SPC MCD 081230 VAZ000-NCZ000-SCZ000-081430- MESOSCALE DISCUSSION 0471 NWS STORM PREDICTION CENTER NORMAN OK 0730 AM CDT SAT APR 08 2006 AREAS AFFECTED...SERN VA/ERN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081230Z - 081430Z SEVERE THREAT -- CURRENTLY LIMITED TO ELEVATED HAIL -- SHOULD INCREASE OVER THE NEXT FEW HOURS AS BOUNDARY LAYER DESTABILIZES. NEW WW MAY BE NEEDED. LATEST RADAR IMAGERY SHOWS AN INCREASE IN CONVECTIVE INTENSITY ACROSS CENTRAL NC ATTM...ABOVE A STABLE BOUNDARY LAYER. INSTABILITY REMAINS LIMITED PER 12Z GSO /GREENSBORO NC/ RAOB...AND THUS WOULD EXPECT ANY SHORT-TERM SEVERE THREAT TO REMAIN IN THE FORM OF MARGINAL HAIL. AS DAYTIME HEATING INTENSIFIES OVER THE NEXT FEW HOURS...EXPECT BOUNDARY LAYER TO SLOWLY DESTABILIZE. WITH SHEAR QUITE FAVORABLE FOR SEVERE STORMS -- AIDED BY 80-PLUS KT MID-LEVEL JET...ANY SURFACE-BASED CONVECTION WOULD LIKELY POSE A THREAT FOR DAMAGING WINDS. THOUGH EWD EXTENT OF THREAT SHOULD REMAIN LIMITED FOR AT LEAST THE NEXT SEVERAL HOURS GIVEN DRY/STABLE LOWER TROPOSPHERE AS REVEALED BY MORNING MHX /MOREHEAD CITY NC/...A CORRIDOR OF SURFACE-BASED SEVERE THREAT MAY EVOLVE FROM THE COASTAL PLAIN OF NC INTO SERN VA. ..GOSS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CAE... 37227835 37867661 36977612 35677683 34447844 34377996 35937930 WWWW From Mcd at goshenarc.org Sat Apr 8 13:38:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 09:38:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081337 SWOMCD SPC MCD 081337 GAZ000-FLZ000-ALZ000-081530- MESOSCALE DISCUSSION 0472 NWS STORM PREDICTION CENTER NORMAN OK 0837 AM CDT SAT APR 08 2006 AREAS AFFECTED...SRN AL...WRN AND CNTRL FL PANHANDLE THROUGH SRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081337Z - 081530Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY NEXT FEW HOURS FROM SRN AL...SRN GA AND INTO THE WRN FL PANHANDLE AND SUBSEQUENTLY SPREAD EWD. SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL AND ISOLATED TORNADOES WILL BE THE PRIMARY THREATS. ISOLATED DAMAGING WIND GUSTS MAY ALSO OCCUR. TORNADO WATCH WILL BE ISSUED SHORTLY. EARLY THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM THE CAROLINAS SWWD THROUGH CNTRL GA AND FARTHER SWWD THROUGH SRN AL. THE WARM SECTOR S OF THIS BOUNDARY IS MOIST WITH BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S. THE ATMOSPHERE IS ALREADY MODERATELY UNSTABLE WITH MLCAPE ON THE ORDER OF 2000 J/KG AND FURTHER DESTABILIZATION WILL OCCUR AS HEATING COMMENCES. STORMS SHOULD CONTINUE DEVELOPING ALONG AND AHEAD OF OUTFLOW BOUNDARY. A WSWLY 40 KT LOW LEVEL JET WILL PERSIST IN THIS REGION WITHIN A ZONE OF HEIGHT FALLS DOWNSTREAM FROM A SEWD MOVING SHORTWAVE TROUGH. DEEP LAYER SHEAR ON THE ORDER OF 50 KT AND FAVORABLE LOW LEVEL HODOGRAPHS WILL SUPPORT SUPERCELLS WITH LOW LEVEL MESOCYCLONES CAPABLE PRODUCING LARGE HAIL AND TORNADOES. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAX...FFC...TAE...BMX...MOB... 31288694 32178536 32458282 31778238 30678317 29828496 30508607 30388752 WWWW From Mcd at goshenarc.org Sat Apr 8 16:02:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 12:02:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081601 SWOMCD SPC MCD 081600 GAZ000-FLZ000-081800- MESOSCALE DISCUSSION 0473 NWS STORM PREDICTION CENTER NORMAN OK 1100 AM CDT SAT APR 08 2006 AREAS AFFECTED...SERN GA THROUGH PORTIONS OF NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081600Z - 081800Z THUNDERSTORMS ARE EXPECTED TO DEVELOP AND SPREAD EWD THROUGH SERN GA AND PORTIONS OF NRN FL BY MID AFTERNOON. A FEW SEVERE STORMS INCLUDING SUPERCELLS WILL BE POSSIBLE. A WW MAY BE NEEDED FOR THIS AREA WITHIN THE NEXT COUPLE HOURS. LATE THIS MORNING A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM ERN SC SWWD THROUGH S CNTRL GA AND FARTHER SW INTO SERN AL. THIS BOUNDARY IS MOVING SLOWLY SEWD. THE WARM SECTOR S OF THIS BOUNDARY IS MODERATELY UNSTABLE WITH MLCAPE FROM 1000 TO 1500 J/KG ACROSS SERN GA AND NRN FL. STRONG SURFACE HEATING OF THE MOIST BOUNDARY LAYER WILL PROMOTE FURTHER DESTABILIZATION INTO THE AFTERNOON. THE MORNING RAOB DATA FROM JACKSONVILLE SHOWED PRESENCE OF A MID LEVEL INVERSION...AND THIS MAY TEND TO INHIBIT DEEP ROBUST CONVECTION A WHILE LONGER. HOWEVER...HEIGHT FALLS AND DEEPER LAYER ASCENT ASSOCIATED WITH AN UPSTREAM SHORTWAVE TROUGH WILL SPREAD SEWD. THIS SHOULD CONTRIBUTE TO THERMODYNAMIC PROFILES MORE CONDUCIVE FOR THUNDERSTORMS THIS AFTERNOON. MID LEVEL JET ON SERN PERIPHERY OF UPPER TROUGH WILL SHIFT SEWD ABOVE THE WSWLY LOW LEVEL JET AND MAINTAIN FAVORABLE VERTICAL SHEAR PROFILES FOR ORGANIZED STORMS INCLUDING SUPERCELLS. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...JAX...FFC... 30128159 29978282 32168297 32398130 31228147 WWWW From Mcd at goshenarc.org Sat Apr 8 17:40:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 13:40:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081739 SWOMCD SPC MCD 081738 NCZ000-081945- MESOSCALE DISCUSSION 0474 NWS STORM PREDICTION CENTER NORMAN OK 1238 PM CDT SAT APR 08 2006 AREAS AFFECTED...ERN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 081738Z - 081945Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY ACROSS COASTAL NC THIS AFTERNOON. POTENTIAL WILL EXIST FOR ORGANIZED SEVERE STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOWS. AREA IS BEING MONITORED FOR A POSSIBLE WW. EARLY THIS AFTERNOON A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM NEAR ELIZABETH CITY SWWD THROUGH ERN SC. A PRE-FRONTAL CONVERGENCE ZONE EXISTS W OF THIS BOUNDARY ACROSS ERN NC FROM NEAR ROCKY MOUNT SWWD TO JUST E OF FLORENCE IN ERN SC. THE ATMOSPHERE IN THE VICINITY OF THESE BOUNDARIES IS DESTABILIZING WITH MLCAPE FROM 500 TO 1000 J/KG. CONVECTIVE INHIBITION APPEARS TO HAVE WEAKENED SUFFICIENTLY TO PROMOTE THUNDERSTORM DEVELOPMENT. THE BEST CHANCE FOR INITIATION APPEARS TO BE ALONG THE OUTFLOW BOUNDARY NEAR COASTAL NC WHERE CONVERGENCE COULD BE LOCALLY ENHANCED BY SEA BREEZE CIRCULATIONS. STRONG LOW LEVEL AND DEEP LAYER SHEAR PROFILES WILL BE SUPPORTIVE OF ORGANIZED STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM... 34327765 34027828 33997867 34277870 34807814 35597741 36307672 36287594 35477584 WWWW From Mcd at goshenarc.org Sat Apr 8 19:01:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 15:01:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 081900 SWOMCD SPC MCD 081900 GAZ000-FLZ000-ALZ000-082100- MESOSCALE DISCUSSION 0475 NWS STORM PREDICTION CENTER NORMAN OK 0200 PM CDT SAT APR 08 2006 AREAS AFFECTED...SERN AL...THE WRN AND CNTRL FL PANHANDLE THROUGH SWRN GA CONCERNING...TORNADO WATCH 173... VALID 081900Z - 082100Z THREAT FOR SEVERE STORMS INCLUDING SUPERCELLS AND LINE SEGMENTS WILL CONTINUE NEXT SEVERAL HOURS. LARGE HAIL...DAMAGING WIND GUSTS AND ISOLATED TORNADOES REMAIN POSSIBLE WITH THE STRONGER STORMS. THIS AFTERNOON A SEWD MOVING OUTFLOW BOUNDARY EXTENDS ACROSS SRN GA INTO SERN AL. MODERATE INSTABILITY EXISTS IN WARM SECTOR S OF THIS BOUNDARY...AND STORMS HAVE INTENSIFIED DURING THE LAST HOUR AS DESTABILIZATION INCREASES. VERTICAL SHEAR PROFILES ARE LARGELY UNIDIRECTIONAL SWLY WITH 0-6 KM SHEAR ON THE ORDER OF 45 KT. STRONGEST LOW LEVEL SHEAR EXISTS OVER SRN GA AND THE FL PANHANDLE WHERE THE SURFACE FLOW REMAINS BACKED TO A MORE SLY DIRECTION. POTENTIAL FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOW ECHOES WILL CONTINUE THROUGH THE AFTERNOON. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB... 30098346 29538669 30968661 31608520 31548322 WWWW From Mcd at goshenarc.org Sat Apr 8 20:23:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 16:23:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082022 SWOMCD SPC MCD 082022 SCZ000-GAZ000-FLZ000-082215- MESOSCALE DISCUSSION 0476 NWS STORM PREDICTION CENTER NORMAN OK 0322 PM CDT SAT APR 08 2006 AREAS AFFECTED...SERN GA EXTREME ERN SC THROUGH NRN FL CONCERNING...TORNADO WATCH 174... VALID 082022Z - 082215Z THREAT FOR LARGE HAIL...ISOLATED TORNADOES AND DAMAGING WIND WILL PERSIST ACROSS SRN GA INTO NRN FL INTO THE EARLY EVENING. THE THREAT ACROSS ERN SC WILL END WITHIN ANOTHER 1-2 HOURS AS THE STORMS MOVE OFFSHORE. STORMS WILL CONTINUE DEVELOPING ALONG AND AHEAD OF SEWD ADVANCING OUTFLOW BOUNDARY ACROSS SRN GA INTO NRN FL NEXT SEVERAL HOURS. THE LATEST RUC FORECASTS A 40 KT WSWLY LOW LEVEL JET WILL PERSIST INTO THE EARLY EVENING OVER NRN FL AND EXTREME SRN GA WITHIN A ZONE OF HEIGHT FALLS ASSOCIATED WITH SEWD ADVANCING SHORTWAVE TROUGH. VWP DATA ACROSS EXTREME SRN GA CONTINUE TO SHOW 0-1 KM STORM RELATIVE HELICITY AROUND 180 M2/S2 FOR ENEWD MOVING STORMS AND DEEP LAYER SHEAR ON THE ORDER OF 50 KT. ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS AND LINE SEGMENTS WITH BOW ECHOES REMAIN LIKELY WITHIN THIS ENVIRONMENT. ..DIAL.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILM...CHS...JAX...TAE... 33227871 32278001 30988138 29768126 29578327 31248308 32328148 33847909 WWWW From Mcd at goshenarc.org Sat Apr 8 21:35:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 17:35:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082134 SWOMCD SPC MCD 082134 NCZ000-082300- MESOSCALE DISCUSSION 0477 NWS STORM PREDICTION CENTER NORMAN OK 0434 PM CDT SAT APR 08 2006 AREAS AFFECTED...FAR ERN NC AND ADJACENT COASTAL WATERS CONCERNING...SEVERE THUNDERSTORM WATCH 175... VALID 082134Z - 082300Z THREAT FOR ISOLATED LARGE HAIL AND DAMAGING WINDS WILL PERSIST ALONG THE ERN NC OUTER BANKS AND ADJACENT COASTAL WATERS FOR THE NEXT 1-2 HOURS. OVERALL SEVERE THREAT WILL CONTINUE TO DIMINISH ACROSS WW 175. STORMS OVER ERN NC HAVE CONSOLIDATED INTO A LINEAR CLUSTER FROM AROUND NCA TO FFA. THIS LINE SHOULD CONTINUE TO MOVE NEWD ACROSS THE OUTER BANKS AND OFFSHORE. 0-6 KM SHEAR VALUES AROUND 70KT PER MHX VAD PROFILER MAY STILL SUPPORT STRONG WINDS BUT INCREASING BOUNDARY LAYER STABILIZATION WILL DIMINISH THE DAMAGING WIND THREAT. FURTHER SOUTH...ADDITIONAL DISCRETE DEVELOPMENT IS STILL POSSIBLE WITH MUCAPES ON THE ORDER OF AROUND 1000 J/KG. COMBINED WITH THE STRONG SHEAR...MARGINALLY SEVERE HAIL POTENTIAL WILL STILL EXIST FOR THE NEXT FEW HOURS ALONG THE OUTER BANKS. ..GRAMS.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...ILM... 33977796 34487760 35177699 35737619 36047577 36097536 35627511 35247523 35017546 34347654 34027733 33467798 33437840 33677853 WWWW From Mcd at goshenarc.org Sat Apr 8 23:01:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 08 Apr 2006 19:01:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 082300 SWOMCD SPC MCD 082259 FLZ000-GAZ000-090030- MESOSCALE DISCUSSION 0478 NWS STORM PREDICTION CENTER NORMAN OK 0559 PM CDT SAT APR 08 2006 AREAS AFFECTED...NRN FL INTO N CNTRL FL PENINSULA CONCERNING...TORNADO WATCH 174...176... VALID 082259Z - 090030Z CONTINUE REMAINING VALID PORTIONS OF WW. ISOLATED SEVERE THREAT MAY DEVELOP INTO NORTH CENTRAL PENINSULA AREAS SOUTH OF WW 174 SHORTLY. HOWEVER...RISK MAY REMAIN MARGINAL ENOUGH TO PRECLUDE THE NEED FOR AN ADDITIONAL WW...AS BELT OF STRONGER FLOW BEGINS TO SHIFT AWAY FROM SOUTH ATLANTIC COASTAL AREAS. TONGUE OF 70F+ DEW POINTS ASSOCIATED WITH BETTER MOIST RETURN FLOW IS READILY EVIDENT IN SURFACE DATA ACROSS THE EASTERN GULF OF MEXICO. THIS EXTENDS THROUGH AREAS NEAR/EAST OF THE FLORIDA BIG BEND INTO SOUTHWARD ADVANCING CONVECTIVE OUTFLOW ACROSS EXTREME SOUTHERN GEORGIA. FORCING ASSOCIATED WITH APPROACHING SOUTHERN BRANCH TROUGH CONTINUES TO AID VIGOROUS CONVECTIVE DEVELOPMENT ALONG OUTFLOW...AND IN WEAK WARM ADVECTION REGIME NOW BEGINNING TO DEVELOP OFF THE NORTHEAST GULF OF MEXICO INTO THE NORTHERN FLORIDA PENINSULA. CONVECTIVE OUTFLOW WILL ADVANCE ACROSS JACKSONVILLE AND THE INTERSTATE 10 CORRIDOR BETWEEN NOW AND 00-01Z...WITH SEVERE THREAT DIMINISHING TO THE NORTH OF BOUNDARY. GUSTY WINDS/LARGE HAIL MAY CONTINUE IN STRONGER CONVECTION ALONG/AHEAD OF BOUNDARY...AND IN NEW DEVELOPMENT ONGOING ALONG EASTERN GULF LOW-LEVEL CONFLUENT ZONE...WHICH WILL GRADUALLY SHIFT INTO COASTAL AREAS FROM NEAR CEDAR KEY THROUGH THE TAMPA AREA THROUGH EARLY EVENING. ..KERR.. 04/08/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TBW...JAX...TAE... 29428446 29858439 30848355 31108253 31168182 31188136 30848074 30138092 29568151 29048189 28618237 28168339 28318395 28778409 29118403 WWWW From Mcd at goshenarc.org Sun Apr 9 14:31:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 10:31:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 091430 SWOMCD SPC MCD 091430 FLZ000-091630- MESOSCALE DISCUSSION 0479 NWS STORM PREDICTION CENTER NORMAN OK 0930 AM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 091430Z - 091630Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY INTO THE AFTERNOON. PRIMARY THREATS WILL BE ISOLATED LARGE HAIL AND DAMAGING WIND GUSTS. WW MAY BE NEEDED FOR PORTIONS OF S FL WITHIN THE NEXT TWO HOURS. LATE THIS MORNING A PRE-FRONTAL SURFACE BOUNDARY EXTENDS ACROSS S CNTRL FL FROM S OF VERO BEACH SWWD TO NEAR FORT MYERS. RICH LOW LEVEL MOISTURE EXISTS IN THE WARM SECTOR BOUNDARY LAYER WITH DEWPOINTS IN THE 70S. THE 12Z RAOB FROM MIAMI SHOWS STEEP MID LEVEL LAPSE RATES ABOVE THE MOIST BOUNDARY LAYER...CONTRIBUTING TO MODERATE INSTABILITY. FURTHER DESTABILIZATION WILL OCCUR AS ANVIL CIRRUS DISSIPATES WITH MLCAPE FROM 2000 TO 2500 J/KG EXPECTED. THE WEAK CAP...DIFFERENTIAL SURFACE HEATING...PRESENCE OF SUBTLE OUTFLOW BOUNDARIES AND POTENTIAL FOR SEA BREEZE CIRCULATIONS WILL CONTRIBUTE TO CONVECTIVE INITIATION INTO THE AFTERNOON. AMBIENT LOW LEVEL FLOW THROUGH 2 KM IS QUITE WEAK AND KINEMATIC PROFILES THROUGH A DEEPER LAYER ARE SUPPORTIVE OF MOSTLY MULTICELLS. HOWEVER...THE THERMODYNAMIC ENVIRONMENT IS FAVORABLE FOR LARGE HAIL WITHIN THE STRONGER STORMS. ..DIAL.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB... 25938015 25338048 25258092 26278145 26828111 27108030 26848006 WWWW From Mcd at goshenarc.org Sun Apr 9 19:44:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 15:44:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 091943 SWOMCD SPC MCD 091943 FLZ000-092145- MESOSCALE DISCUSSION 0480 NWS STORM PREDICTION CENTER NORMAN OK 0243 PM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FL CONCERNING...SEVERE THUNDERSTORM WATCH 177... VALID 091943Z - 092145Z THUNDERSTORMS WILL CONTINUE DEVELOPING OVER PORTIONS OF THE SRN FL PENINSULA THIS AFTERNOON. ISOLATED LARGE HAIL AND DAMAGING WIND WILL REMAIN A THREAT WITH THE STRONGER STORMS. BOUNDARIES...SEVERAL OF WHICH APPEAR TO BE ENHANCED BY SEABREEZE CIRCULATIONS...PERSIST ACROSS THE SRN FL PENINSULA. ONE SUCH BOUNDARY EXTENDS FROM NEAR SARASOTA SEWD TO N OF LAKE OKEECHOBEE. OTHER BOUNDARIES EXIST FROM S OF LAKE OKEECHOBEE TO NEAR MIAMI. THE ATMOSPHERE REMAINS MODERATELY UNSTABLE WITH MINIMAL CAP...AND STORMS SHOULD CONTINUE DEVELOPING NEXT FEW HOURS. VERTICAL SHEAR PROFILES ARE WLY UNIDIRECTIONAL...GENERALLY AOB 25 KT AND SUPPORTIVE OF MULTICELLS. ACTIVITY MAY REMAIN MORE LIMITED OVER THE SWRN FL PENINSULA WHERE SURFACE HEATING HAS BEEN MODERATED BY ANVIL DEBRIS. ALSO DEWPOINTS HAVE BEEN IN THE PROCESS OF MIXING DOWNWARD SIGNIFICANTLY ALONG PORTIONS OF THE SWRN COAST...POSSIBLY DUE IN PART TO THE INFLUENCE OF CONVECTIVE OUTFLOW FROM THE OFFSHORE MCS. ..DIAL.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...TBW... 25988012 25458039 25528076 26588149 27228244 27488214 27238134 27418041 26878011 WWWW From Mcd at goshenarc.org Sun Apr 9 22:42:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 09 Apr 2006 18:42:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 092241 SWOMCD SPC MCD 092241 FLZ000-092315- MESOSCALE DISCUSSION 0481 NWS STORM PREDICTION CENTER NORMAN OK 0541 PM CDT SUN APR 09 2006 AREAS AFFECTED...SRN FLORIDA CONCERNING...SEVERE THUNDERSTORM WATCH 177... VALID 092241Z - 092315Z WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 23Z. STRONGER MID-LEVEL FORCING...ASSOCIATED WITH WEAK IMPULSE EMBEDDED WITHIN BROADER SCALE UPPER TROUGHING WHICH ENCOMPASSES MUCH OF THE SOUTHEASTERN STATES AND EASTERN GULF OF MEXICO...APPEARS TO BE SHIFTING EAST OF THE SOUTHERN FLORIDA PENINSULA. LINGERING LOW-LEVEL CONVERGENCE NEAR SYNOPTIC FRONT...SOUTH OF VERO BEACH/TAMPA...REMAINS A FOCUS FOR CONVECTIVE DEVELOPMENT. HOWEVER...COOLING/DRYING OF BOUNDARY LAYER HAS ALREADY OCCURRED ACROSS MUCH OF THE SOUTHERN PENINSULA...AND POTENTIAL FOR ADDITIONAL SEVERE THUNDERSTORMS BEFORE NIGHTFALL SEEMS LIMITED IN SHEAR REGIME ONLY MARGINALLY SUPPORTIVE OF UPDRAFT ROTATION. ..KERR.. 04/09/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MFL...MLB...EYW...TBW... 27058243 27288198 27508112 27608026 27757984 27137948 25807972 24758014 24218150 23878170 23548178 23608296 24178316 24818311 25028206 25218153 25588185 26088226 26498254 26658252 WWWW From Mcd at goshenarc.org Mon Apr 10 22:51:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 10 Apr 2006 18:51:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 102249 SWOMCD SPC MCD 102249 SDZ000-NDZ000-MTZ000-110015- MESOSCALE DISCUSSION 0482 NWS STORM PREDICTION CENTER NORMAN OK 0549 PM CDT MON APR 10 2006 AREAS AFFECTED...WRN DAKOTAS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 102249Z - 110015Z VISIBLE IMAGERY SUGGESTS RATHER VIGOROUS CONVECTIVE DEVELOPMENT IS UNDERWAY ACROSS THE NORTHERN HIGH PLAINS...NORTH OF REDIG SD. THIS APPEARS TO HAVE BEEN AIDED BY MID-LEVEL COOLING/LIFT ASSOCIATED WITH SHORT WAVE TROUGH LIFTING NORTHEAST OF THE NORTH CENTRAL ROCKIES THIS AFTERNOON. STRONGEST LARGE-SCALE ASCENT AND STEEPENING LAPSE RATES HAVE BECOME FOCUSED NEAR DEVELOPING SURFACE LOW...WHICH IS PROGGED TO MIGRATE OUT OF SOUTHEAST MONTANA INTO SOUTHWESTERN NORTH DAKOTA BY 02-03Z. THOUGH LOW-LEVEL MOISTURE IS LIMITED...WITH SURFACE DEW POINTS ONLY IN THE LOWER 40S...RUC INDICATES MOST UNSTABLE CAPE FOR HEATED SURFACE-BASED PARCELS MAY BE AS HIGH AS 1000 J/KG. EMBEDDED WITHIN MODERATELY SHEARED ENVIRONMENT...MARGINALLY SUPPORTIVE OF UPDRAFT ROTATION...ISOLATED STRONGER STORMS COULD PRODUCE HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS. MAIN SEVERE THREAT...HOWEVER...MAY BE POTENTIAL FOR DOWNBURSTS AND STRONG GUSTY SURFACE WINDS IN DRY DEEP MIXED BOUNDARY LAYER. ADDITIONAL ISOLATED STORMS MAY DEVELOP OFF THE BLACK HILLS THROUGH EARLY EVENING...BEFORE CONVECTIVE POTENTIAL DIMINISHES FAIRLY QUICKLY AFTER DARK WITH LOSS OF DAYTIME HEATING. ..KERR.. 04/10/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ABR...BIS...UNR...BYZ...GGW... 45880421 46660404 47040378 47380278 46850146 46130175 45000217 44500175 43830229 43960328 44570374 44920392 WWWW From Mcd at goshenarc.org Tue Apr 11 23:00:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 11 Apr 2006 19:00:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 112259 SWOMCD SPC MCD 112258 IAZ000-MOZ000-KSZ000-NEZ000-120030- MESOSCALE DISCUSSION 0483 NWS STORM PREDICTION CENTER NORMAN OK 0558 PM CDT TUE APR 11 2006 AREAS AFFECTED...NE KS...SE NEB...SW IA...NW MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 112258Z - 120030Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. CONVECTIVE INITIATION IS UNDERWAY EAST OF CONCORDIA KS INTO THE BEATRICE NEB AREA...WHERE 80 KT 500 MB JET STREAK IS ENHANCING FORCING FOR UPWARD VERTICAL MOTION AHEAD OF EASTWARD ADVANCING SURFACE FRONT. PRE-FRONTAL LOW-LEVEL THERMAL RIDGE AXIS HAS BECOME FOCUS FOR DESTABILIZATION THIS AFTERNOON...WITH SURFACE TEMPERATURES INCREASING INTO THE LOWER/MID 80S AS DEW POINTS CLIMBED TO NEAR 50F. THIS APPEARS TO BE SUPPORTING CAPE AROUND 750 J/KG AS CAP IS BROKEN. INSTABILITY MAY BE SUFFICIENT TO SUPPORT HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS AS BROKEN LINE OF STORMS CONTINUES TO EVOLVE IN FAVORABLY SHEARED ENVIRONMENT. HOWEVER...RISK OF DAMAGING WIND GUSTS MAY BE PRIMARY SEVERE THREAT. EVAPORATIVE COOLING IN DRY...DEEP MIXED BOUNDARY LAYER PROBABLY WILL ENHANCE DOWNDRAFTS...AND DOWNWARD TRANSFER OF MOMENTUM ASSOCIATED WITH BELT OF 40 TO 50 KT MEAN CLOUD BEARING LAYER FLOW ACCOMPANYING UPPER JET. ISOLATED DAMAGING WIND POTENTIAL SHOULD DIMINISH BY 02-03Z AS BOUNDARY LAYER BEGINS TO COOL/STABILIZE. ..KERR.. 04/11/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP... 40719629 41319578 41869565 42519523 42539423 41759382 40659474 39909535 39399609 39039673 39199713 39879704 WWWW From Mcd at goshenarc.org Wed Apr 12 02:51:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 11 Apr 2006 22:51:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 120249 SWOMCD SPC MCD 120249 ILZ000-IAZ000-WIZ000-MOZ000-KSZ000-120415- MESOSCALE DISCUSSION 0484 NWS STORM PREDICTION CENTER NORMAN OK 0949 PM CDT TUE APR 11 2006 AREAS AFFECTED...ERN IA...PARTS OF NRN MO...SW WI...NW IL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 120249Z - 120415Z SEVERE POTENTIAL IS EXPECTED TO DIMINISH NEXT FEW HOURS. FORCING IN EXIT REGION OF CYCLONIC MID-LEVEL JET STREAK...FOCUSED ALONG/AHEAD OF WEAKENING SURFACE LOW/COLD FRONT...HAS PROGRESSED THROUGH NARROW TONGUE OF STRONGER SURFACE BASED INSTABILITY...WHERE LAPSE RATES BECAME QUITE STEEP THIS AFTERNOON WITH DAYTIME HEATING. THOUGH RUC GUIDANCE SUGGESTS UPPER SPEED MAXIMUM IS WEAKENING...MID- LEVEL COOLING/LIFT MAY MAINTAIN SUFFICIENT DESTABILIZATION FOR CONTINUATION OF THUNDERSTORM ACTIVITY EASTWARD ACROSS THE REMAINDER OF IOWA/NORTHERN MISSOURI BY 06Z. RELATIVE HUMIDITIES BELOW CLOUD BASES LIKELY WILL REMAIN SUFFICIENTLY LOW TO ENHANCE DOWNDRAFTS... AND SOME RISK FOR GUSTY SURFACE WINDS...BUT THIS SEEMS LIKELY TO BECOME MORE SPORADIC IN COOLER/COOLING BOUNDARY LAYER. POTENTIAL FOR MARGINALLY SEVERE HAIL WILL ALSO DROP OFF IN COOLER LOW-LEVEL ENVIRONMENT WITH WEAKER LAPSE RATES IN CLOSER PROXIMITY TO THE MISSISSIPPI RIVER. ..KERR.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...ARX...DMX...EAX...TOP... 42329329 43379286 43249109 43059089 42349053 41579058 40879081 40439123 39479224 38849372 38199599 39479474 40299390 41059332 WWWW From Mcd at goshenarc.org Wed Apr 12 17:37:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 13:37:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 121735 SWOMCD SPC MCD 121735 OHZ000-MIZ000-INZ000-122000- MESOSCALE DISCUSSION 0485 NWS STORM PREDICTION CENTER NORMAN OK 1235 PM CDT WED APR 12 2006 AREAS AFFECTED...EXTREME SERN LWR MI...EXTREME NERN IND...NRN/CNTRL OH CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 121735Z - 122000Z TSTMS WILL DEVELOP SWD FROM SRN LWR MI INTO EXTREME NERN IND EARLY THIS AFTN...THEN MOVE EWD AND BECOME STRONGER IN NRN/CNTRL OH AFTER 21Z. A FEW STORMS MAY PRODUCE DAMAGING WINDS...LARGE HAIL AND PERHAPS AN ISOLD TORNADO AND A WW MAY BE NEEDED WITHIN THE HOUR. WELL-DEFINED UPPER VORTICITY CENTER WAS MOVING ACROSS LWR MI AT 30 KTS AND WILL BE OVER SWRN ONTARIO BY 22Z. TRAILING TROUGH PASSED THE WLC INDIANA PROFILER AROUND 15Z AND WILL SWING EWD ACROSS SERN LWR MI AND NRN/CNTRL OH THROUGH EARLY EVENING. CORRESPONDING SFC REFLECTION...IN THE FORM OF CONVERGENCE...WILL BE THE IMPETUS FOR TSTM INITIATION FROM SCNTRL/SERN LWR MI INTO NERN IND EARLY THIS AFTN. MESOANALYSIS SHOWS A TONGUE OF 50-55 DEGREE F DEW POINTS ADVECTING NEWD AHEAD OF THE FRONT COINCIDENT WITH THE STEEPEST LOW-LEVEL LAPSE RATES. THIS WILL BE SUFFICIENT TO SUPPORT TSTMS ALONG/AHEAD OF THE FRONT THIS AFTN. TAMDAR/ACAR SOUNDINGS FROM KTOL/KDTW EXHIBIT VERY STRONG LOW-LEVEL WIND FIELDS WITH 45+ KTS JUST OFF THE SFC...WITH FLOW TURNING WNWLY ABOVE 3 KM. THIS IS BOOSTING VERTICAL AND LOW-LEVEL SHEAR VALUES TO SUPPORT BRIEF SUPERCELL STRUCTURES. MEAN-SHEAR VECTORS IN THE 2-6KM LAYER NEARLY NORMAL TO THE INITIATING BOUNDARY SUGGESTS THAT THERE COULD BE DISCRETE STRUCTURES. BUT...EVOLUTION INTO A MIX OF LINEAR AND DISCRETE CELLS WILL BE LIKELY OWING TO STRONG FORCING. STRONGER STORMS WILL BE CAPABLE OF LARGE HAIL GIVEN STEEP MID-LEVEL LAPSE RATES...AND DAMAGING WINDS WILL BE LIKELY. ISOLD TORNADOES CANNOT BE RULED OUT GIVEN THE MAGNITUDE OF LOW-LEVEL SHEAR. ..RACY.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PBZ...RLX...CLE...ILN...DTX...IWX...GRR...IND... 40028464 41098545 42288478 42728387 42568300 42148184 41658115 40728064 39948188 39768301 39718411 WWWW From Mcd at goshenarc.org Wed Apr 12 20:06:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 16:06:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122004 SWOMCD SPC MCD 122004 ARZ000-MOZ000-OKZ000-122200- MESOSCALE DISCUSSION 0486 NWS STORM PREDICTION CENTER NORMAN OK 0304 PM CDT WED APR 12 2006 AREAS AFFECTED...EXTREME SRN MO...EXTREME NERN OK...NRN AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122004Z - 122200Z SFC ANALYSIS PLACES AN E-W ORIENTED BOUNDARY ACROSS NRN OK AND AR. WEAK CONVERGENCE ALONG THE FRONT...AND STRONG BOUNDARY LAYER HEATING HAS BEEN SUFFICIENT FOR ISOLD TSTM INITIATION ACROSS NRN AR. VSBL SATL SHOWS ADDITIONAL CUMULUS GROWING THE LENGTH OF THE FRONT FROM EAST OF KTUL TO JUST WEST OF THE MO BOOTHEEL. THOUGH THE FLOW IN THE BOUNDARY LAYER-3KM LAYER IS WEAK...STRONGER FLOW EXISTS ABOVE...BOOSTING 6KM SHEAR INTO THE 30-35 KT RANGE. THIS SUGGESTS THAT MAINLY ISOLD MULTICELL STORMS WILL EXIST WITH SLOW STORM MOTION TO THE SOUTHEAST AROUND 20 KTS. NONETHELESS...SHALLOW INVERTED-V STRUCTURE IN THE BOUNDARY LAYER AND STEEP LAPSE RATES ABOVE WILL BE SUFFICIENT FOR GUSTY WINDS AND PERHAPS MARGINALLY SEVERE HAIL. ..RACY.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF...TSA... 36669435 36539360 36319211 36129134 35679149 35559231 35659331 36139504 WWWW From Mcd at goshenarc.org Wed Apr 12 21:06:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 17:06:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122104 SWOMCD SPC MCD 122104 TXZ000-122330- MESOSCALE DISCUSSION 0487 NWS STORM PREDICTION CENTER NORMAN OK 0404 PM CDT WED APR 12 2006 AREAS AFFECTED...WRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122104Z - 122330Z PREDOMINATELY SUB-SEVERE CONVECTION IS EXPECTED TO DEVELOP ACROSS WRN CENTRAL TX THROUGH THE AFTERNOON...WITH LOCALLY STRONG WINDS AND SMALL HAIL POSSIBLE. LATEST VISIBLE IMAGERY INDICATES TCU EXTENDING FROM S OF CDS TO E OF MAF...ALONG SOON TO BE RETREATING DRYLINE AND WITHIN SURFACE PRESSURE TROUGH. ALTHOUGH LOW LEVEL CONVERGENCE IS WEAK...CONTINUED HEATING WILL ALLOW FOR AT LEAST ISOLATED THUNDERSTORMS TO DEVELOP. SHEAR PROFILES ARE WEAK THROUGHOUT THE COLUMN DUE TO UPPER HIGH OVERHEAD. THUS...ONLY PULSE TYPE CONVECTION IS ANTICIPATED. GIVEN 1000-1500 MLCAPE AND RELATIVELY DRY SUB-CLOUD LAYER...STRONG WIND GUSTS...AND EVEN SOME SMALL HAIL MAY OCCUR. ADDITIONAL DEVELOPMENT MAY OCCUR ON ANY OUTFLOW BOUNDARIES THAT DEVELOP...WITH DECREASING THREAT AFTER SUNSET. ..JEWELL.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...SJT...LUB...MAF... 34069952 32529999 31780094 31520127 32440215 33100177 33970118 34390057 34450004 WWWW From Mcd at goshenarc.org Wed Apr 12 22:09:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 12 Apr 2006 18:09:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 122208 SWOMCD SPC MCD 122207 PAZ000-NYZ000-WVZ000-OHZ000-122300- MESOSCALE DISCUSSION 0488 NWS STORM PREDICTION CENTER NORMAN OK 0507 PM CDT WED APR 12 2006 AREAS AFFECTED...NERN OH/NWRN PA/FAR WRN NY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 122207Z - 122300Z ISOLATED DAMAGING WIND GUSTS AND MARGINALLY SEVERE HAIL WILL BE POSSIBLE THROUGH 00-01Z ACROSS NERN OH/NWRN PA AND POSSIBLY INTO FAR WRN NY. BAND OF STORMS EXTENDING FROM SRN ONTARIO SWWD ACROSS LAKE ERIE TO NORTH CENTRAL OH WILL CONTINUE TO SPREAD EWD AT 45 KT. ALTHOUGH INSTABILITY IS VERY WEAK EAST OF THIS ACTIVITY...SLIGHTLY GREATER INSTABILITY /MLCAPE 500 J/KG/ ACROSS WRN OH/NRN KY IS BEING FED INTO NERN OH PER A 40-50 KT SWLY LLJ. STRONG FORCING SPREADING ACROSS THE LOWER GREAT LAKES/UPPER OH VALLEY REGION AT THIS TIME WILL MAINTAIN ORGANIZED LINEAR STRUCTURE...BUT 40-50 KT EFFECTIVE SHEAR ORIENTED NORMAL TO BAND OF STORMS SHOULD ALSO SUPPORT DISCRETE STRUCTURES. STRONGER CORES WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS... GIVEN STRONG WINDS IN THE LOWER TROPOSPHERE /AROUND 50 KT JUST BELOW 1 KM AGL PER CLE WSR-88D VAD/ AND INVERTED-V THERMODYNAMIC PROFILES /25-35 DEGREE SURFACE DEWPOINT DEPRESSIONS/ FAVORING DOWNWARD MOMENTUM TRANSPORT. MARGINALLY SEVERE HAIL WILL ALSO BE POSSIBLE. HOWEVER...WEAK INSTABILITY IS EXPECTED TO LIMIT OVERALL SEVERE THREAT/COVERAGE. ..PETERS.. 04/12/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BUF...CTP...PBZ...CLE... 41008245 41378166 42088075 42547936 42317906 40917948 40628045 40558209 40598261 WWWW From Mcd at goshenarc.org Thu Apr 13 16:53:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 12:53:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 131651 SWOMCD SPC MCD 131651 VAZ000-131845- MESOSCALE DISCUSSION 0489 NWS STORM PREDICTION CENTER NORMAN OK 1151 AM CDT THU APR 13 2006 AREAS AFFECTED...PARTS OF NW INTO CNTRL VA CONCERNING...CONVECTIVE TRENDS VALID 131651Z - 131845Z DESPITE INCREASING MID-LEVEL SUBSIDENCE ACROSS PARTS OF THE UPPER OHIO VALLEY...THROUGH AND INTO THE LEE OF THE CENTRAL APPALACHIANS ...SURFACE HEATING AND OROGRAPHY HAVE PROVEN SUFFICIENT TO SUPPORT INITIATION OF CONVECTION. THIS IS OCCURRING OFF THE HIGHER TERRAIN TO THE NORTH/NORTHWEST CHARLOTTESVILLE...WHERE MOST UNSTABLE CAPE NOW APPEARS TO BE ON THE ORDER OF 1500 J/KG. EMBEDDED WITHIN MODERATELY STRONG NORTHWESTERLY MID/UPPER FLOW... CONVECTION IS EXPECTED TO PROPAGATE INTO/THROUGH THE CHARLOTTESVILLE AREAS BY 18-19Z...WHEN DEVELOPING STORMS MAY BECOME ROOTED IN A DEEP MIXED BOUNDARY LAYER WITH SIZABLE TEMPERATURE/DEW POINT SPREADS. HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS MAY OCCUR IN STRONGER CELLS...AND DOWNBURSTS ALSO APPEARS POSSIBLE. HOWEVER... GIVEN LACK OF MORE FAVORABLE MID/UPPER SUPPORT FOR UPWARD VERTICAL MOTION...STRONGER STORMS SEEM LIKELY TO REMAIN ISOLATED...AND ANY SEVERE THREAT RATHER HIGHLY LOCALIZED. ..KERR.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 38767828 38767786 38377751 37857743 37577809 37547856 37257915 37177984 37358002 37657975 38137936 38447912 38667866 WWWW From Mcd at goshenarc.org Thu Apr 13 22:01:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 18:01:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 132159 SWOMCD SPC MCD 132159 WIZ000-ILZ000-IAZ000-MNZ000-140000- MESOSCALE DISCUSSION 0490 NWS STORM PREDICTION CENTER NORMAN OK 0459 PM CDT THU APR 13 2006 AREAS AFFECTED...SERN MN / NERN IA / SWRN WI CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 132159Z - 140000Z MODIFIED TAMDAR/ACARS SOUNDINGS SHOW A NEARLY UNCAPPED ENVIRONMENT WHERE IT HAS HEATED INTO THE UPPER 80S...ALONG LEADING EDGE OF HIGHER SURFACE DEWPOINTS STRETCHING ACROSS CENTRAL IA TOWARD ALO. VISIBLE IMAGERY INDICATED INCREASING CU FIELD ACROSS WRN IA WHERE IT HAS BECOME HOT...WITH RECENT TAMDAR SOUNDING SHOWING VERY DEEP MIXED LAYER EXTENDING TO 700 MB WITH ONLY UPPER 40S DEWPOINTS. ALTHOUGH CU FIELD IS INCREASING OVER W CENTRAL IA...FOCUS FOR DEVELOPMENT REMAINS WEAK...WITH MODEST LOW LEVEL CONVERGENCE WITHIN SURFACE TROUGH. MOST LIKELY AREA FOR DEEP CONVECTIVE INITIATION WILL BE FARTHER NE ALONG WARM FRONT INTO NERN IA/SERN MN/SWRN WI WHERE CONVERGENCE WILL BE STRONGEST AND BENEATH WEAKER CAP. 18Z PARALLEL NAM RUN INDICATES STORMS DEVELOPING AROUND 00Z OVER SERN MN WITH MORE ISOLATED DEVELOPMENT INTO ERN IA. IF THIS OCCURS...A FEW SUPERCELLS WILL BE POSSIBLE GIVEN STRONG SHEAR PROFILES...WITH MAINLY A LARGE HAIL THREAT...TRANSITIONING TO A DAMAGING WIND THREAT WITH TIME AS STORMS EVOLVE SEWD AND COLD POOL GROWS. ..JEWELL.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...LOT...MKX...DVN...ARX...MPX...DMX... 45189142 44719003 43568900 42658884 42038910 41619037 41559125 41739222 42329388 43019448 43579395 43989356 44879314 45079246 WWWW From Mcd at goshenarc.org Thu Apr 13 23:14:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 19:14:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 132312 SWOMCD SPC MCD 132312 NYZ000-PAZ000-140015- MESOSCALE DISCUSSION 0491 NWS STORM PREDICTION CENTER NORMAN OK 0612 PM CDT THU APR 13 2006 AREAS AFFECTED...PARTS OF CENTRAL/SRN NY INTO FAR NERN PA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 132312Z - 140015Z ISOLATED STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS CENTRAL/SRN NY INTO FAR NERN PA THROUGH 00-01Z...WITH ACTIVITY DECREASING AFTER SUNSET WITH THE ONSET OF BOUNDARY LAYER STABILIZATION. EXIT REGION OF WNWLY 60 KT MID-LEVEL JET MAX OVER LAKE HURON/LAKE ERIE COMBINED WITH COLD 500 MB TEMPERATURES /-22 TO -24 C/ WILL MAINTAIN THUNDERSTORM POTENTIAL THROUGH THE EARLY EVENING. 30-35 KT OF EFFECTIVE SHEAR AND STEEP LAPSE RATES WILL SUPPORT HAIL AS THE PRIMARY THREAT...BUT WEAK INSTABILITY WILL CONTINUE TO LIMIT SEVERE COVERAGE. ..PETERS.. 04/13/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ALY...BGM...BUF...CTP... 43207809 43227659 43487602 43417553 43057527 42527442 41747524 41767676 42557814 WWWW From Mcd at goshenarc.org Fri Apr 14 01:00:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 21:00:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140058 SWOMCD SPC MCD 140058 ILZ000-WIZ000-IAZ000-MNZ000-140230- MESOSCALE DISCUSSION 0492 NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT THU APR 13 2006 AREAS AFFECTED...ERN IA / SWRN WI / NRN IL CONCERNING...SEVERE THUNDERSTORM WATCH 178... VALID 140058Z - 140230Z THREAT FOR LARGE HAIL AND DAMAGING WINDS CONTINUES WITHIN WW 178. FARTHER E...ANOTHER WW WILL BE ISSUED FOR MUCH OF NRN IL AND FAR SRN WI. CLUSTER OF SUPERCELLS WILL CONTINUE TO MOVE EWD AND WILL LIKELY MERGE INTO ONE LARGE MCS WITH THE MAIN THREAT BEING DAMAGING WINDS AS IT SHIFTS EWD INTO IL AND SRN WI. THREAT OF BRIEF TORNADOES WITH INDIVIDUAL SUPERCELLS EXISTS...HOWEVER PARTICULARLY DAMAGING WINDS WITH STRONG MESOCYCLONES APPEARS MORE LIKELY AND RELATIVELY LOW BOUNDARY LAYER RH SUGGEST ANY TORNADOES WOULD BE BRIEF. THIS THREAT...HOWEVER...WILL DECREASE WITH TIME AS STORMS MERGE. ALTHOUGH INSTABILITY DIRECTLY AHEAD OF MCS IS WEAK AS SEEN ON 00Z ILX SOUNDING...SWLY LOW LEVEL JET WILL CONTINUE TO FUEL SYSTEM FROM THE SW. GIVEN LARGE TEMPERATURE/DEWPOINT SPREADS IN THE BOUNDARY LAYER DOWNSTREAM...ENHANCED DOWNDRAFT WINDS COULD RESULT. THEREFORE...A NEW WW WILL BE NEEDED E OF CURRENT WATCH. FARTHER N INTO WRN WI AND SERN MN...ENOUGH SHEAR AND INSTABILITY REMAIN FOR SVR TSTORMS WITH ADDITIONAL ACTIVITY NOW DEVELOPING ACROSS FAR WRN WI ALONG WARM FRONT. THIS WILL LIKELY POSE A WIND AND HAIL THREAT BUT TO A LESSER DEGREE COMPARED TO ACTIVITY TO THE SOUTH WHERE INSTABILITY POOL IS LARGER. ..JEWELL.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...LOT...ILX...MKX...DVN...ARX...MPX...DMX... 40438757 41099387 44269319 44739194 44879131 43788782 43088794 WWWW From Mcd at goshenarc.org Fri Apr 14 01:09:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 21:09:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140107 SWOMCD SPC MCD 140106 WIZ000-MNZ000-140230- MESOSCALE DISCUSSION 0493 NWS STORM PREDICTION CENTER NORMAN OK 0806 PM CDT THU APR 13 2006 AREAS AFFECTED...WEST CENTRAL INTO CENTRAL WI CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 140106Z - 140230Z THUNDERSTORMS...WITH AN ATTENDANT SEVERE POTENTIAL...EXPECTED TO INCREASE IN AREAL COVERAGE BY MID EVENING /AROUND 03Z/ ACROSS WEST CENTRAL WI THEN SPREAD ESEWD. WW MAY BE REQUIRED NORTH OF WW 178 FOR PARTS OF CENTRAL WI. LATEST LIGHTNING DATA/SATELLITE IMAGERY SUGGESTS CONVECTIVE ACTIVITY CURRENTLY SPREADING EWD ACROSS ERN ND/NERN SD IS ASSOCIATED WITH LEADING EDGE OF DEEPER LARGE SCALE ASCENT WITH SRN CANADA/ND SHORT WAVE TROUGH. WEAK INSTABILITY OVER ERN ND SHOULD LIMIT THE SEVERE THREAT WITH PRESENT ACTIVITY OVER THAT REGION. AT 00Z...A WARM FRONT EXTENDED FROM EAST CENTRAL MN SEWD ACROSS NRN IL/NRN IND. STRENGTHENING SSWLY LLJ ACROSS ERN IA/IL INTO CENTRAL WI WILL PROVIDE A FEED OF GREATER MOISTURE/INSTABILITY TO MAINTAIN STORMS ONCE THEY DEVELOP ALONG/N OF WARM FRONT INTO CENTRAL WI. THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE OVER WEST CENTRAL WI /POTENTIALLY ERN MN/ BY 03Z AS THE ASCENT NOW LOCATED OVER ERN ND/SD ENCOUNTERS THE GREATER INSTABILITY FARTHER EAST. HAIL SHOULD BE THE PRIMARY THREAT AS MUCH OF THIS EXPECTED NEW DEVELOPMENT WILL LIKELY BE ELEVATED. ..PETERS.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GRB...DLH...ARX...MPX... 44549253 44909294 45839293 45839129 45508972 45088889 44288914 44299023 44629096 44639195 WWWW From Mcd at goshenarc.org Fri Apr 14 03:33:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 13 Apr 2006 23:33:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 140331 SWOMCD SPC MCD 140331 OHZ000-MIZ000-INZ000-WIZ000-ILZ000-IAZ000-140430- MESOSCALE DISCUSSION 0494 NWS STORM PREDICTION CENTER NORMAN OK 1031 PM CDT THU APR 13 2006 AREAS AFFECTED...FAR ERN IA/CENTRAL-SRN WI/NRN IL/FAR NWRN IND CONCERNING...SEVERE THUNDERSTORM WATCH 178...179... VALID 140331Z - 140430Z SEVERE STORMS EXPECTED TO CONTINUE ACROSS MAINLY SERN PART OF WW 178 AND MUCH OF WW 179. NEW WW MAY BE NEEDED FOR SWRN LOWER MI AND CENTRAL/NRN IND BY 04Z. HP SUPERCELL CURRENTLY LOCATED OVER THE IL COUNTIES OF ROCK ISLAND...MERCER AND HENRY SHOULD CONTINUE TO MOVE SEWD ALONG MOISTURE/INSTABILITY AXIS WHICH EXTENDED SEWD INTO CENTRAL TO SERN IL. MEANWHILE...STRONGEST LEFT MOVING STORMS OVER NRN IL/SRN WI HAVE MOVED N OF WARM FRONT SUGGESTING THREAT WITH THIS ACTIVITY SHOULD BE HAIL AS THEY CONTINUE TO TRACK ENE AT 50-55 KT. 50 KT SSWLY LLJ EXTENDING FROM ERN MO INTO NRN IL/SRN WI WILL CONTINUE TO PROVIDE INFLUX OF MODERATE INSTABILITY INTO ONGOING MCS ACROSS FAR ERN IA/NRN IL/SRN WI. LLJ IS EXPECTED TO VEER TO SWLY AND TRANSLATE EWD EXTENDING INTO SRN LOWER MI OVERNIGHT. THIS WILL AID DESTABILIZATION FOR MCS TO CONTINUE TO SPREAD EWD WITH ATTENDANT THREAT FOR SEVERE STORMS. ..PETERS.. 04/14/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...APX...IWX...GRR...IND...GRB...LOT...ILX...MKX...DVN...ARX... 44348669 43538471 41598477 39748486 39768887 40249019 40739065 41059115 41439137 42569140 43339124 44359065 45048999 45128960 44748719 WWWW From Mcd at goshenarc.org Sat Apr 15 00:53:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 20:53:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150051 SWOMCD SPC MCD 150051 INZ000-ILZ000-150215- MESOSCALE DISCUSSION 0504 NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT FRI APR 14 2006 AREAS AFFECTED...NORTHEAST/EAST CENTRAL IL INTO CENTRAL INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 150051Z - 150215Z TORNADO WATCHES 185/187 CONTINUE UNTIL 05Z. PRIMARY TORNADO THREAT /INCLUDING THE POTENTIAL FOR A FEW STRONG TORNADOES/ CONTINUES FROM NORTHEAST IL/FAR EAST CENTRAL IL INTO CENTRAL INDIANA. A POTENTIALLY DANGEROUS SITUATION MAY DEVELOP INTO THE INDIANAPOLIS METRO AREA BY 02Z/10 PM LOCAL TIME. SCATTERED SUPERCELLS /WITH HISTORY OF TORNADOES/ CONTINUE FROM NORTHEAST IL INTO CENTRAL INDIANA AT THIS TIME. PRIMARY TORNADO POTENTIAL...INCLUDING THE POSSIBILITY FOR A STRONG TORNADO OR TWO...OVER THE NEXT SEVERAL HOURS WILL REMAIN IN AREAS ALONG/JUST NORTH OF QUASI-STATIONARY OUTFLOW BOUNDARY/EFFECTIVE BAROCLINIC ZONE THAT IS ROUGHLY ORIENTED NW-SE FROM NEAR KANKAKEE IL INTO CENTRAL INDIANA NEAR LAFAYETTE AND THE INDIANAPOLIS METRO AREA. AIDED BY A SUB-SYNOPTIC SURFACE LOW...THIS CORRIDOR IS CHARACTERIZED BY A RATHER UNSTABLE AIRMASS /00Z LINCOLN IL RAOB/...BACKED LOW LEVEL FLOW/ENLARGED LOW LEVEL HODOGRAPHS...AND A MOIST ENVIRONMENT FAVORABLE FOR A STRONG TORNADO OR TWO OVER THE NEXT COUPLE OF HOURS. INTENSE SUPERCELL IN MONTGOMERY/TIPPECANOE COUNTIES INDIANA MAY APPROACH THE INDIANAPOLIS METRO AREA BY AROUND 02Z. VERY LARGE HAIL/DAMAGING WINDS REMAINS POSSIBLE AS WELL WITH THESE ONGOING SUPERCELLS. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX...DVN... 40339030 41138935 41668811 41008656 40348503 39158544 39138691 39588959 39849025 WWWW From Mcd at goshenarc.org Sat Apr 15 01:14:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 21:14:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150112 SWOMCD SPC MCD 150112 VAZ000-PAZ000-MDZ000-WVZ000-OHZ000-KYZ000-150245- MESOSCALE DISCUSSION 0505 NWS STORM PREDICTION CENTER NORMAN OK 0812 PM CDT FRI APR 14 2006 AREAS AFFECTED...ERN-SERN OH/SW-SOUTH CENTRAL PA/WV/WRN-NRN VA/WRN MD CONCERNING...SEVERE THUNDERSTORM WATCH 186... VALID 150112Z - 150245Z ...EAST OF WW 186... AREA OF STRONG-SEVERE STORMS EXTENDING FROM FAR SWRN PA THROUGH ERN WV WILL CONTINUE TO MOVE EWD NEXT FEW HOURS...BUT OVERALL SEVERE THREAT EXPECTED TO DECREASE AS THIS ACTIVITY CONTINUES TO MOVE INTO THE HIGHER TERRAIN. STABILIZATION PROCESS IS EXPECTED TO CONTINUE ALONG/E OF THE CENTRAL APPALACHIANS /EAST OF WW 186/ GIVEN THE LOSS OF DAYTIME HEATING...AS HAS BEEN INDICATED ACROSS PARTS OF CENTRAL VA DURING THE LAST HOUR /SINCE 2330Z/. GIVEN THIS TREND AND LIMITED TIME/SPACE OF SEVERE THREAT EAST OF WW 186...A NEW WW IS NOT WARRANTED. STEEP LOW-MID LEVEL LAPSE RATES PER RNK/IAD 00Z SOUNDINGS SUGGEST ISOLATED STRONG WIND GUSTS/HAIL WILL BE POSSIBLE WITH THE STRONGER CORES THROUGH 02-03Z. ...PART OF SOUTH CENTRAL OH/WRN WV... AIR MASS ACROSS THIS PART OF WW 186 IS EXPECTED TO REMAIN MODERATELY UNSTABLE SUPPORTING A CONTINUED THREAT FOR SEVERE STORMS. UPSTREAM STORMS...CURRENTLY LOCATED ACROSS SWRN OH/SERN IND...SHOULD TRACK ESE INTO SWRN PART OF WW 186 BY 02-03Z. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...JKL...ILN... 39538266 39088087 40287902 39887777 38797761 37617895 36918031 37188152 38038268 38828278 WWWW From Mcd at goshenarc.org Sat Apr 15 03:40:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 14 Apr 2006 23:40:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150339 SWOMCD SPC MCD 150338 OHZ000-KYZ000-INZ000-150515- MESOSCALE DISCUSSION 0506 NWS STORM PREDICTION CENTER NORMAN OK 1038 PM CDT FRI APR 14 2006 AREAS AFFECTED...PARTS OF CENTRAL-SERN IND/SWRN OH/NRN KY CONCERNING...TORNADO WATCH 187...188... VALID 150338Z - 150515Z SEVERE THREAT EXPECTED TO CONTINUE ACROSS CENTRAL/SERN IND INTO PARTS OF CINCINNATI METRO AREA THROUGH 05Z. THEREAFTER... STABILIZING AIR MASS IN WAKE OF ACTIVITY ACROSS CENTRAL/SRN OH SHOULD LIMIT SEVERE THREAT FARTHER SEWD INTO SOUTH CENTRAL OH AND THE REST OF NRN KY. LATE EVENING SURFACE MESO-ANALYSIS INDICATED AN OUTFLOW BOUNDARY EXTENDED FROM WEST CENTRAL IND /WARREN AND FOUNTAIN COUNTIES/ SEWD ACROSS FAR NRN KY /JUST S OF CVG/ AND THEN ESEWD INTO NERN KY TO CENTRAL WV. SEVERAL ROUNDS OF THUNDERSTORMS ACROSS MUCH OF SWRN OH HAVE CONVECTIVELY OVERTURNED/STABILIZED THE AIR MASS ALONG/N OF THIS OUTFLOW BOUNDARY. 50 KT WSWLY LLJ LOCATED ACROSS THE LOWER OH VALLEY SHOULD AID IN MAINTAINING DESTABILIZATION/SHEAR TO SUPPORT ONGOING CENTRAL/SERN IND STORM CLUSTERS AS THIS ACTIVITY REACHES THE CINCINNATI METRO AREA BETWEEN 04-05Z. DAMAGING WINDS/LARGE HAIL SHOULD BE THE PRIMARY THREATS WITH THIS ACTIVITY WITH AN ISOLATED TORNADO STILL POSSIBLE WITH ANY STORMS INTERACTING WITH THE OUTFLOW BOUNDARY WHERE LOW-LEVEL SHEAR SHOULD REMAIN ENHANCED. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...JKL...ILN...LMK...IWX...IND... 38938684 39818675 40478590 40388455 39758276 38298321 38358481 38748564 38678674 WWWW From Mcd at goshenarc.org Sat Apr 15 04:07:34 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 00:07:34 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150405 SWOMCD SPC MCD 150405 VAZ000-WVZ000-OHZ000-KYZ000-150500- MESOSCALE DISCUSSION 0507 NWS STORM PREDICTION CENTER NORMAN OK 1105 PM CDT FRI APR 14 2006 AREAS AFFECTED...PART OF SOUTH CENTRAL OH AND CENTRAL/SRN WV CONCERNING...SEVERE THUNDERSTORM WATCH 186... VALID 150405Z - 150500Z WW 186 WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 05Z. MOST OF THE AIR MASS ACROSS VALID PART OF WW 186 FROM SOUTH CENTRAL OH INTO CENTRAL/SRN WV HAS BEEN CONVECTIVELY OVERTURNED BY EARLIER AND ONGOING THUNDERSTORMS...WITH ANY ASSOCIATED SEVERE THREAT HAVING DECREASED CONSIDERABLY DURING THE LAST HOUR. STRONGEST STORMS AT THIS TIME ARE LOCATED WELL UPSTREAM AROUND THE CINCINNATI OH AREA... WITH THIS ACTIVITY LIKELY WEAKENING PRIOR TO REACHING WW 186. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX...JKL...ILN... 39238259 39088171 38427965 38018007 37898074 37208143 37178166 37608227 38518280 WWWW From Mcd at goshenarc.org Sat Apr 15 04:19:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 00:19:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150417 SWOMCD SPC MCD 150417 INZ000-150445- MESOSCALE DISCUSSION 0508 NWS STORM PREDICTION CENTER NORMAN OK 1117 PM CDT FRI APR 14 2006 AREAS AFFECTED...PARTS OF CENTRAL/SERN IND CONCERNING...TORNADO WATCH 187... VALID 150417Z - 150445Z WW 187 WILL BE ALLOWED TO EXPIRE AT 05Z. STRONGEST STORMS WITHIN VALID PART OF WW 187 WERE LOCATED OVER RUSH/ DECATUR COUNTIES AND MOVING SEWD AT 40 KT. OVERALL DECREASING TREND IN SEVERE THREAT EXPECTED TO CONTINUE AS THIS ONGOING ACTIVITY MOVES INTO MAINLY THE SRN HALF OF WW 188 BY 0430-05Z. ..PETERS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IWX...IND... 38918683 39818642 40468560 40448493 39298540 38888559 38768604 38678665 WWWW From Mcd at goshenarc.org Sat Apr 15 06:36:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 02:36:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 150634 SWOMCD SPC MCD 150634 VAZ000-150830- MESOSCALE DISCUSSION 0509 NWS STORM PREDICTION CENTER NORMAN OK 0134 AM CDT SAT APR 15 2006 AREAS AFFECTED...SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 150634Z - 150830Z THUNDERSTORMS MAY POSE A THREAT FOR ISOLATED HAIL AND STRONG WIND GUSTS AS THEY MOVE THROUGH SWRN VA NEXT FEW HOURS. TRENDS WILL CONTINUE TO BE MONITORED FOR INTENSIFICATION. EARLY THIS MORNING A SMALL CLUSTER OF STORMS CONTINUES OVER SWRN VA NEAR TIMBERLAKE. ACTIVITY IS DEVELOPING ALONG THE LEADING EDGE OF AN OUTFLOW BOUNDARY THAT CONTINUES TO SPREAD ESEWD. OBJECTIVE ANALYSIS SHOWS THE DOWNSTREAM ATMOSPHERE IS MODERATELY UNSTABLE WITH MUCAPE FROM 1500 TO 2000 J/KG AND A MODEST CAP. RECENT SURFACE OBSERVATIONS SHOW WIND GUSTS AROUND 31 KT ALONG THE GUST FRONT. GUST FRONT CONVERGENCE AND THE MODEST CAP SUGGEST STORMS MAY CONTINUE TO DEVELOP EWD NEXT FEW HOURS. THE BOUNDARY LAYER HAS UNDERGONE SOME STABILIZATION AND COOLING...AND THIS MAY SERVE AS AN OVERALL LIMITING FACTOR. HOWEVER...STEEP MID LEVEL LAPSE RATES AND MODERATE MUCAPE SUGGEST THE STRONGER STORMS MAY BE CAPABLE OF PRODUCING HAIL. INCREASING LOW-MID LEVEL WLY KINEMATIC PROFILES ASSOCIATED WITH A SHORTWAVE TROUGH MOVING ESEWD TOWARD THE MID ATLANTIC MAY ALSO ENHANCE POTENTIAL FOR ISOLATED STRONG WIND GUSTS. ..DIAL.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 37947906 37517802 36927827 36757915 37638006 WWWW From Mcd at goshenarc.org Sat Apr 15 17:01:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 13:01:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151700 SWOMCD SPC MCD 151659 NJZ000-PAZ000-DEZ000-MDZ000-VAZ000-DCZ000-151800- MESOSCALE DISCUSSION 0510 NWS STORM PREDICTION CENTER NORMAN OK 1159 AM CDT SAT APR 15 2006 AREAS AFFECTED...SERN PA...SRN NJ...DELMARVA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151659Z - 151800Z POTENTIAL FOR SEVERE THUNDERSTORMS EXPECTED TO INCREASE ACROSS PORTIONS OF SERN PA...SRN NJ...AND THE DELMARVA REGION INTO THE AFTERNOON. A SEVERE THUNDERSTORM WATCH MAY BE NEEDED IN THE NEXT HOUR OR SO. ISOLATED CONVECTION APPEARS TO BE DEVELOPING NEAR COLD FRONT/LEE-TROUGH INTERSECTION NOW OVER SERN PA. AIR MASS AHEAD OF THIS DEVELOPMENT WAS BECOMING INCREASINGLY UNSTABLE WITH LATEST DIAGNOSTIC DATA INDICATING MLCAPE AROUND 1000 J/KG FROM ERN/NRN VA TO SRN NJ. ANOTHER HOUR OR SO OF HEATING SHOULD EFFECTIVELY ELIMINATE REMAINING INHIBITION AND CONTRIBUTE TO INCREASING STORM INITIATION ACROSS THE REGION. EFFECTIVE SHEAR WILL SUPPORT STORM ORGANIZATION AND INTENSIFICATION AND A FEW SUPERCELLS WITH HAIL APPEAR POSSIBLE. IN ADDITION...STORMS FORMING AND MERGING AHEAD OF THE FRONT AND LEE-TROUGH COULD EVOLVE INTO FAST MOVING SMALL SCALE LINE SEGMENTS WITH SCATTERED WIND DAMAGE POSSIBLE FROM THIS ACTIVITY. A SEVERE THUNDERSTORM WATCH MAY BE NEEDED IN THE NEXT HOUR OR SO TO COVER PARTS OF THE AREA THROUGH EARLY EVENING. ..CARBIN.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...CTP...LWX...RNK... 40287565 40257461 39707424 37877536 36947597 36727688 36927768 37327878 37907901 39337731 39887678 WWWW From Mcd at goshenarc.org Sat Apr 15 18:17:11 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 14:17:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151815 SWOMCD SPC MCD 151814 SDZ000-151945- MESOSCALE DISCUSSION 0511 NWS STORM PREDICTION CENTER NORMAN OK 0114 PM CDT SAT APR 15 2006 AREAS AFFECTED...SOUTHERN SD CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151814Z - 151945Z THREAT FOR ISOLATED LARGE HAIL MAY INCREASE THROUGH EARLY/MID AFTERNOON ACROSS SOUTHERN SD. GIVEN EXPECTED MARGINAL/ISOLATED NATURE...A SEVERE WATCH IS NOT CURRENTLY ANTICIPATED...BUT CONVECTIVE TRENDS WILL BE MONITORED. ARC OF TSTMS HAS RECENTLY INCREASED IN INTENSITY ACROSS SOUTHERN SD...LIKELY TIED TO INCREASING ELEVATED INSTABILITY VIA DRYSLOT/FORCING FOR ASCENT ASSOCIATED WITH CENTRAL HIGH PLAINS CYCLONE. 17Z RUC/09Z NAMKF SOUNDINGS SUGGEST MUCAPE WILL GENERALLY REMAIN AT 300-500 J/KG OR LESS ACROSS MUCH OF SOUTHERN SD. GIVEN THE ELEVATED NATURE OF BUOYANCY...LARGE HAIL WOULD BE THE PRIMARY HAZARD. CURRENT EXPECTATIONS ARE THAT THE THREAT WILL REMAIN SUFFICIENTLY MARGINAL/ISOLATED GIVEN MODEST INSTABILITY/CLOUD BEARING SHEARING SUCH THAT A WATCH MAY NOT BE NEEDED...HOWEVER WILL CONTINUE TO MONITOR. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FSD...ABR...UNR... 43230242 44080258 44760155 44709833 43429766 43169945 43150077 WWWW From Mcd at goshenarc.org Sat Apr 15 18:45:14 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 14:45:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151843 SWOMCD SPC MCD 151842 NJZ000-DEZ000-MDZ000-PAZ000-VAZ000-DCZ000-WVZ000-OHZ000-151945- MESOSCALE DISCUSSION 0512 NWS STORM PREDICTION CENTER NORMAN OK 0142 PM CDT SAT APR 15 2006 AREAS AFFECTED...UPPER OH VALLEY EAST TO SRN NJ/DELMARVA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151842Z - 151945Z AREAS ALONG AND SOUTH OF SLOW MOVING COLD FRONT...FROM SERN OH... ACROSS WV...TO DELMARVA AND SRN NJ...ARE STILL BEING MONITORED FOR A POSSIBLE SEVERE THUNDERSTORM WATCH THIS AFTERNOON. HOWEVER...RECENT TRENDS IN RADAR IMAGERY SUGGEST STORM DEVELOPMENT IS OCCURRING SLOWER THAN EARLIER EXPECTED. WAVE CLOUDS OVER AND DOWNWIND FROM THE APPALACHIAN CREST APPEAR TO BE SLOWLY ERODING AS DEEPER MIXING/HEATING CONTINUES ACROSS THE REGION AHEAD OF A SLOW MOVING FRONT. BOUNDARY LAYER WAS MOST UNSTABLE ACROSS NRN/ERN VA INTO MD ATTM AND STORMS MAY INCREASE OVER THIS AREA WHERE LEE-TROUGH/FRONT CONVERGENCE IS MAXIMIZED OVER THE NEXT 1-2 HOURS. FARTHER WEST...LIFT ALONG THE FRONTAL ZONE SHOULD BE SUFFICIENT FOR AT LEAST ISOLATED STORMS IN MODERATELY UNSTABLE ENVIRONMENT. STRONG NWLY FLOW ALOFT WILL PERSIST ACROSS THE REGION AND RESULT IN DEEP LAYER SHEAR SUPPORTIVE OF STORM ORGANIZATION. PRIMARY LIMITING FACTOR APPEARS TO BE LACK OF GREATER LARGE SCALE FORCING FOR ASCENT AND THIS COULD LIMIT OVERALL STORM COVERAGE. IF AN AREA OF GREATER SEVERE STORM POTENTIAL BECOMES CLEARER IN THE NEXT HOUR OR SO...A WATCH IS STILL POSSIBLE FOR DEVELOPING/EVOLVING CONVECTION. ..CARBIN.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PHI...AKQ...CTP...LWX...RNK...PBZ...RLX...ILN... 38338039 38558253 39108304 39348192 39767974 39697725 39837517 39757439 38777481 38237539 38137602 38047797 WWWW From Mcd at goshenarc.org Sat Apr 15 19:10:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 15:10:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 151909 SWOMCD SPC MCD 151908 NEZ000-KSZ000-152115- MESOSCALE DISCUSSION 0513 NWS STORM PREDICTION CENTER NORMAN OK 0208 PM CDT SAT APR 15 2006 AREAS AFFECTED...WEST CENTRAL/CENTRAL INTO EXTREME NORTH CENTRAL KS/EASTERN NEB CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 151908Z - 152115Z SEVERE THREAT IS LIKELY TO INCREASE ACROSS MUCH OF WEST CENTRAL/CENTRAL NEB INTO EXTREME NORTH CENTRAL KS/EASTERN NEB THROUGH MID AFTERNOON. A WATCH APPEARS LIKELY BY 20-21Z. CU FIELD CONTINUES TO EVOLVE ACROSS SOUTHWEST INTO CENTRAL NEB WITHIN WELL MIXED BOUNDARY LAYER...AHEAD OF SURFACE LOW NEAR NORTH PLATTE NEB AND IN VICINITY OF QUASI-STATIONARY FRONT/DRYLINE TRIPLE POINT. GIVEN AMPLE INSOLATION/WEAKENING SURFACE BASED INHIBITION AND INCREASINGLY STRONG FORCING FOR ASCENT ACROSS WEST CENTRAL/CENTRAL NEB...INITIATION OF DEEP CONVECTION APPEARS LIKELY IN THE NEXT FEW HOURS. PRIMARY HAZARDS WILL LIKELY BE LARGE HAIL AND DAMAGING WIND GUSTS...ATTRIBUTABLE TO MODEST INSTABILITY AND WELL MIXED BOUNDARY LAYER. SOME THREAT FOR TORNADOES MAY EXIST GIVEN AMBIENT VERTICAL VORTICITY/STEEP LAPSE RATE ENVIRONMENT IN OTHERWISE MARGINAL MOISTURE /UPPER 40S TO MIDDLE 50S SURFACE DEWPOINTS/. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OAX...GID...LBF... 41050041 41210144 42610157 42709844 42229754 40239689 39999795 40819917 WWWW From Mcd at goshenarc.org Sat Apr 15 20:50:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 16:50:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152048 SWOMCD SPC MCD 152048 MOZ000-OKZ000-KSZ000-152215- MESOSCALE DISCUSSION 0514 NWS STORM PREDICTION CENTER NORMAN OK 0348 PM CDT SAT APR 15 2006 AREAS AFFECTED...EASTERN KS/NORTHEAST OK INTO WESTERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152048Z - 152215Z MONITORING CONVECTIVE TRENDS FOR SURFACE BASED STORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS EAST CENTRAL KS INTO OK. A WATCH COULD BE NEEDED IN THE NEXT FEW HOURS...NAMELY ACROSS EASTERN KS INTO WESTERN MO. MID LEVEL CONVECTION ABOVE WELL CAPPED BOUNDARY LAYER -- REFERENCE SPECIAL 18Z RAOBS FROM TOPEKA KS/SPRINGFIELD MO -- HAS PERSISTED MUCH OF THE AFTERNOON ACROSS EASTERN KS...WITH RELATIVELY NEWER MID LEVEL DEVELOPMENT ACROSS NORTHEAST KS IN AREAS NORTH/WEST OF TULSA. WHILE THIS ACTIVITY COULD POSE A HAIL THREAT AS IT PROGRESSES ENE INTO MO...PRIMARY SEVERE THREAT/SURFACE BASED DEVELOPMENT MAY DEVELOP IN VICINITY OF DRYLINE ACROSS EAST CENTRAL KS...CURRENTLY FROM NEAR CONCORDIA-SALINA TO WICHITA...AND PERHAPS EVEN INTO NORTH CENTRAL/NORTHEAST OK. BOUNDARY LAYER CU HAS EVOLVED OVER THE PAST HALF HOUR INVOF THE DRYLINE. WHILE LIKLIHOOD/EXTENT OF SURFACE BASED CONVECTION REMAINS UNCLEAR...STRONG HEATING COUPLED WITH FORCING FOR ASCENT ASSOCIATED WITH CENTRAL HIGH PLAINS CYCLONE MAY LEAD TO INITIATION OF DEEP CONVECTION LATE THIS AFTERNOON/EARLY EVENING. COMBINATION OF MODERATE INSTABILITY/AMPLE EFFECTIVE BULK SHEAR WOULD BE FAVORABLE FOR SUPERCELLS...WITH ATTENDANT THREATS OF LARGE HAIL/DAMAGING WINDS. TORNADO THREAT MAY INCREASE AS STORMS DEVELOP EASTWARD ACROSS FAR EASTERN KS INTO WESTERN MO EARLY THIS EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN... 39169705 39529616 39829434 39379332 37409354 36579502 36419683 37369744 WWWW From Mcd at goshenarc.org Sat Apr 15 21:50:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 17:50:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152148 SWOMCD SPC MCD 152148 OKZ000-TXZ000-152315- MESOSCALE DISCUSSION 0515 NWS STORM PREDICTION CENTER NORMAN OK 0448 PM CDT SAT APR 15 2006 AREAS AFFECTED...CENTRAL OK/FAR NORTH CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152148Z - 152315Z MONITORING FOR HIGHLY CONDITIONAL/ISOLATED SEVERE THREAT ACROSS CENTRAL OK INTO FAR NORTH CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. A WATCH IS NOT ANTICIPATED. MONITORING EVOLUTION OF POCKETS OF HIGH BASED BOUNDARY LAYER CU IN VICINITY OF DRYLINE ACROSS CENTRAL OK INTO NORTH CENTRAL TX. LATEST ANALYSIS/OBSERVATIONAL TRENDS FEATURES STRONG MIXING/WEAKENING SURFACE BASED CINH -- WITH TEMPERATURES OVER 100F IN SOUTHWEST OK -- AND AMPLE MASS CONVERGENCE INVOF DRYLINE FROM WEST OF THE OKC METRO AREA TO NEAR DUNCAN OK AND EAST OF WICHITA FALLS TX. IN THIS CORRIDOR...VIA DEEP MIXING/GLANCING UPPER SUPPORT...SOME POTENTIAL EXISTS FOR A STORM OR TWO TO DEVELOP LATE THIS AFTERNOON/EARLY EVENING ACROSS CENTRAL OK/NORTH CENTRAL TX. CONDITIONAL POTENTIAL WOULD EXIST FOR LARGE HAIL AND STRONG WIND GUSTS THROUGH EARLY EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...FWD...OUN... 35909754 36239665 35749615 34009656 33429750 33949844 WWWW From Mcd at goshenarc.org Sat Apr 15 22:02:56 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 18:02:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152201 SWOMCD SPC MCD 152200 IAZ000-MOZ000-KSZ000-NEZ000-SDZ000-152330- MESOSCALE DISCUSSION 0516 NWS STORM PREDICTION CENTER NORMAN OK 0500 PM CDT SAT APR 15 2006 AREAS AFFECTED...CENTRAL/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO CONCERNING...TORNADO WATCH 190... VALID 152200Z - 152330Z TORNADO WATCH 190 CONTINUES UNTIL 03Z ACROSS CENTRAL/EASTERN NEB AND NORTHEAST KS. AN ADDITIONAL TORNADO WATCH WILL BE ISSUED SOON FOR WESTERN IA AND NORTHWEST MO. AMBIENT ENVIRONMENT REMAINS FAVORABLE FOR SUPERCELLS AND LARGE HAIL/ISOLATED TORNADOES ACROSS MUCH OF CENTRAL/EASTERN NEB AND NORTHEAST KS...FOCUSED INVOF DRYLINE AND OCCLUSION/WARM FRONT TRIPLE POINT. TORNADOES HAVE ALREADY BEEN REPORTED IN GAGE COUNTY NEB. IN PRESENCE OF MODERATE INSTABILITY/AMPLE VERTICAL SHEAR...STORMS WILL CONTINUE TO DEVELOP EASTWARD EARLY THIS EVENING INTO WESTERN IA/NORTHWEST MO...WITH STORMS POTENTIALLY BREACHING THE EASTERN EXTENT OF TORNADO WATCH 190 BY AROUND 23Z. FLOW FIELDS WILL REMAIN FAVORABLE FOR ROTATING STORMS/ISOLATED TORNADOES...WITH LOW LEVEL MOISTURE CONTINUING TO INCREASE ALONG THE MISSOURI RIVER ACROSS NORTHWEST MO/SOUTHWEST IA EARLY THIS EVENING. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP...GID...LBF... 42459827 42569653 42419426 41389305 39839303 39219392 39309571 40189639 41279710 41809867 WWWW From Mcd at goshenarc.org Sat Apr 15 23:01:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:01:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152259 SWOMCD SPC MCD 152259 MDZ000-VAZ000-NCZ000-WVZ000-160030- MESOSCALE DISCUSSION 0517 NWS STORM PREDICTION CENTER NORMAN OK 0559 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS WV...VA...MD...DE...DC CONCERNING...SEVERE THUNDERSTORM WATCH 189...191... VALID 152259Z - 160030Z PRONOUNCED SUPERCELL WITH REFLECTIVITY HOOK HAS MOVED SEWD OFFSHORE CAPE CHARLES REGION AND OVER ATLANTIC. STRONGEST VERTICAL SHEAR PROFILES ARE EVIDENT FROM SRN DELMARVA PENINSULA SWD ALONG COASTAL FRONT INTO EXTREME NERN NC...W OF WHICH SFC FLOW IS WLY. SFC MESOANALYSIS SHOWS COLD FRONT AND ATTENDANT SFC DRYING/VEERING FROM SERN PA SWWD ACROSS SRN WV. AIR MASS IN BETWEEN THESE BOUNDARIES REMAINS CHARACTERIZED BY STRONG HEATING AND SFC DEW POINTS GENERALLY IN 50S F...EXCEPT ACROSS SRN WV WHERE MIXING HAS YIELDED 40S F VALUES. LACK OF SUBSTANTIAL CONVERGENCE IN THIS AIR MASS WILL CONTINUE TO LIMIT CONVECTIVE COVERAGE...THOUGH ANY SUSTAINED TSTMS SUCH AS THOSE MOVING SEWD ACROSS NORTHUMBERLAND COUNTY VA MAY PRODUCE DAMAGING WIND AND LARGE HAIL FROM THERE ACROSS SRN CHESAPEAKE BAY TO PORTIONS SRN ACCOMACK/NORTHAMPTON COUNTIES. VIS IMAGERY AND REFLECTIVITY TRENDS INDICATE SEVERE TSTM POTENTIAL HAS DIMINISHED SUBSTANTIALLY ACROSS WV...EWD ACROSS PORTIONS WRN/CENTRAL/NRN VA...EWD TO CENTRAL/NRN DELMARVA REGION. OVERALL CONVECTIVE COVERAGE AND INTENSITY SHOULD CONTINUE TO DIMINISH DURING NEXT FEW HOURS WITH LOSS OF DIURNAL HEATING AND INCREASING SBCINH. ..EDWARDS.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...LWX...RNK... 38097978 38357952 38467927 38587744 38477584 38347518 38177480 37727504 37097542 36557552 36487599 36577867 37727859 WWWW From Mcd at goshenarc.org Sat Apr 15 23:19:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:19:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152317 SWOMCD SPC MCD 152317 IAZ000-MOZ000-KSZ000-NEZ000-SDZ000-160045- MESOSCALE DISCUSSION 0518 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CDT SAT APR 15 2006 AREAS AFFECTED...NORTHERN/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO CONCERNING...TORNADO WATCH 190...192... VALID 152317Z - 160045Z VALID PORTION OF TORNADO WATCH 190 CONTINUES UNTIL 03Z...TORNADO WATCH 192 CONTINUES UNTIL 05Z. ISOLATED TORNADO AND LARGE HAIL/DAMAGING WIND THREAT CONTINUES ACROSS VALID PORTIONS OF TORNADO WATCHES 190/192 THIS EVENING FROM NORTHERN/EASTERN NEB AND NORTHEAST KS INTO WESTERN IA/NORTHWEST MO. POTENTIALLY SIGNIFICANT TORNADO DAMAGE WAS REPORTED EARLIER NEAR BEATRICE NEB. WITHIN THESE TORNADO WATCHES...RELATIVELY GREATEST TORNADO POTENTIAL THROUGH EARLY EVENING APPEARS TO BE FROM EXTREME SOUTHEAST NEB/FAR NORTHEAST KS INTO SOUTHWEST IA AND NORTHWEST MO...INCLUDING AREAS FROM TOPEKA KS-ST JOSEPH MO-MARYVILLE MO TO RED OAK/CRESTON IA. IN THIS CORRIDOR...SCATTERED SUPERCELLS ARE ONGOING AND LIKELY TO PERSIST IN RATHER FAVORABLE ENVIRONMENT INVOF DRYLINE AND WARM FRONT/OCCLUSION. THE NEAR STORM ENVIRONMENT IS CHARACTERIZED BY BACKED SOUTHEASTERLY WINDS AND BOUNDARY LAYER DEWPOINTS IN THE LOWER 60S/SURFACE TEMP-DEWPOINT DEPRESSIONS OF 15-20 F. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...EAX...FSD...OAX...TOP...LBF... 42689901 42569653 42119481 41249313 39839303 39219392 38529576 39989591 41399685 42049893 WWWW From Mcd at goshenarc.org Sat Apr 15 23:43:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 19:43:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 152341 SWOMCD SPC MCD 152341 IAZ000-MNZ000-NEZ000-SDZ000-160115- MESOSCALE DISCUSSION 0519 NWS STORM PREDICTION CENTER NORMAN OK 0641 PM CDT SAT APR 15 2006 AREAS AFFECTED...SOUTHEAST SD/NORTHWEST IA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 152341Z - 160115Z SEVERE THREAT MAY DEVELOP THROUGH EARLY/MID EVENING ACROSS FAR SOUTHEAST SD INTO NORTHWEST IA. ALTHOUGH A SEVERE TSTM WATCH IS NOT CURRENTLY ANTICIPATED...WILL CONTINUE TO MONITOR CONVECTIVE TRENDS ON NORTHERN PERIPHERY OF TORNADO WATCHES 190/192. ARC OF STRONG/SEVERE TSTMS...WITH SOME EMBEDDED SUPERCELLS AND HISTORY OF LARGE HAIL...EXTENDS ACROSS FAR NORTHEAST NEB TO ALONG THE NEB/IA BORDER AS OF 2340Z. AS THIS ACTIVITY SPREADS FURTHER EAST/NORTHEAST...AT LEAST AN ISOLATED THREAT MAY EXTEND INTO FAR SOUTHEAST SD/NORTHWEST IA THIS EVENING. WITH WARM SECTOR/RICHER THETA-E REMAINING SUFFICIENTLY SOUTH OF THE AREA...PRIMARY SEVERE HAZARD WOULD BE LARGE HAIL. LATEST RUC FORECAST SOUNDINGS SUGGEST POTENTIAL FOR 500-1000 J/KG ELEVATED MUCAPE...MAXIMIZED THIS EVENING ACROSS NORTHWEST IA. ..GUYER.. 04/15/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DMX...FSD... 43229733 43629730 43659624 43289332 42399331 42309464 42379615 42509665 WWWW From Mcd at goshenarc.org Sun Apr 16 02:16:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 22:16:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160214 SWOMCD SPC MCD 160214 MOZ000-IAZ000-KSZ000-160345- MESOSCALE DISCUSSION 0520 NWS STORM PREDICTION CENTER NORMAN OK 0914 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS ERN KS...NWRN MO...WRN IA CONCERNING...TORNADO WATCH 192... VALID 160214Z - 160345Z BROKEN LINE OF SEVERE TSTMS FROM MKC AREA NNEWD TO SW OF DSM INCLUDED AT LEAST TWO POTENTIALLY TORNADIC SUPERCELLS AS OF 2Z -- IN N-CENTRAL/NERN PORTIONS KC METRO AND DEKALB/DAVIESS COUNTY MO. ALL MODES OF SEVERE REMAIN POSSIBLE FROM THIS BAND AS IT MOVES ENEWD ACROSS NWRN MO AND S-CENTRAL IA NEXT 2-3 HOURS. MEANWHILE SEVERE POTENTIAL IS INCREASING OVER PORTIONS E-CENTRAL KS AND W-CENTRAL MO S OF WW 192 WILL BE MONITORED FOR POSSIBLE WW. MODIFIED TOP RAOB AND RUC SOUNDINGS INDICATE EFFECTIVE LAYER PARCELS -- IN INFLOW REGION OF NWRN MO CONVECTION -- MAY BECOME INCREASINGLY ELEVATED ABOVE SFC THROUGH ABOUT 4Z...INDICATING GRADUAL DECREASE IN TORNADO AND SEVERE WIND POTENTIAL. MEANWHILE...LARGE LOW LEVEL HODOGRAPHS AND FAVORABLE DEEP-LAYER SHEAR WILL SUPPORT SUPERCELLS...WITH 0-3 KM SRH UP TO NEAR 600 J/KG AND MLCAPES 1000-1500 J/KG IN PROFILER/VWP DATA AND MODIFIED MODEL SOUNDINGS. FARTHER SW...SFC MESOANALYSIS SHOWS COLD FRONT HAS MERGED WITH DRYLINE ACROSS PORTIONS ERN KS -- FROM LWC AREA SWWD ACROSS COWLEY COUNTY. THIS PROCESS SHOULD CONTINUE/PROPAGATE SWWD ALONG DRYLINE INTO S-CENTRAL KS AND N-CENTRAL OK. CONVECTION HAS DEVELOPED ALONG COMBINED BOUNDARY FROM LWC TO GREENWOOD COUNTY KS...IN ZONE OF MAXIMIZED LOW LEVEL CONVERGENCE ASSOCIATED WITH FRONTAL/DRYLINE ASCENT. STRONG CINH IS EVIDENT ACROSS NRN OK...SO EVEN WITH FRONTAL LIFT...BACKBUILDING SHOULD BE LIMITED TO N OF KS/OK BORDER. DEEP-LAYER WIND AND SHEAR VECTORS HAVE SIGNIFICANT COMPONENT PARALLEL TO FORCING BOUNDARY...SUPPORTING CONTINUED LINEAR MODE. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...SGF...DMX...EAX...TOP...ICT... 37739608 38259548 38999491 39409419 39879392 40269383 40699392 41269415 41909489 42209441 42149350 41209257 40319232 39489228 38929285 38129401 37779547 WWWW From Mcd at goshenarc.org Sun Apr 16 03:48:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 15 Apr 2006 23:48:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160346 SWOMCD SPC MCD 160346 ILZ000-IAZ000-WIZ000-MOZ000-160545- MESOSCALE DISCUSSION 0521 NWS STORM PREDICTION CENTER NORMAN OK 1046 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS E-CENTRAL/SERN IA...NERN MO...EXTREME NWRN IL. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 160346Z - 160545Z BAND OF STRONG-SEVERE TSTMS NOW OVER ERN-MOST PORTIONS WW 192 IS EXPECTED TO LIFT NEWD TO AREA BETWEEN CID-UIN THROUGH APPROXIMATELY 7Z. MAIN SEVERE POTENTIAL WILL TRANSITION TO HAIL...WITH OCCASIONAL STRONG-SEVERE GUSTS ALSO POSSIBLE PARTICULARLY OVER MO. AREA WILL BE MONITORED FOR POSSIBLE WW. VERTICAL SHEAR PROFILES ARE STRENGTHENING WITH TIME ACROSS THIS AREA AS MID/UPPER LEVEL SPEED MAX APCHS...ASSOCIATED WITH NEARLY VERTICALLY STACKED LOW OVER ERN NEB. HOWEVER...GIVEN DECELERATION OF THAT CYCLONE AND FCST MOTION OF MAIN BAND OF LOW LEVEL CONVECTIVE FORCING...PRIND ACTIVITY WILL OUTRUN EWD SPREAD OF OPTIMAL DEEP-LAYER SHEAR AS WELL. INFLOW PARCELS ARE FCST TO BECOME MORE ELEVATED OFF SFC WITH TIME AND WITH NWD EXTENT...GIVEN COMBINATION OF DIABATIC SFC COOLING AND PRECIP COOLING OVER IA. PARCELS MAY REMAIN NEARLY SFC-BASED FOR ANOTHER FEW HOURS ACROSS PORTIONS NERN MO...WHERE BOTH MUCAPE AND SEVERE POTENTIAL SHOULD BE MAXIMIZED. EFFECTIVE SHEARS 35-50 KT ARE EVIDENT IN RUC FCST SOUNDINGS BOTH FOR CONVECTION ROOTED IN 800-900 MB LAYER OVER IA...AND ANYWHERE BETWEEN SFC-850 MB ACROSS NERN MO. MUCAPES 1000-1500 J/KG ARE EXPECTED. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...ARX...DMX...EAX... 39289238 39849236 40049231 40539233 40749256 41079272 41529289 42019304 42869341 43339222 43239153 42539058 41929022 40909043 40489075 39419178 39249222 WWWW From Mcd at goshenarc.org Sun Apr 16 04:41:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 00:41:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 160439 SWOMCD SPC MCD 160439 MOZ000-ILZ000-160545- MESOSCALE DISCUSSION 0522 NWS STORM PREDICTION CENTER NORMAN OK 1139 PM CDT SAT APR 15 2006 AREAS AFFECTED...PORTIONS WRN/NRN MO AND CENTRAL/SRN IA. CONCERNING...TORNADO WATCH 192... VALID 160439Z - 160545Z CONVECTIVE COVERAGE/INTENSITY...AND ACCORDINGLY SEVERE POTENTIAL...IS DIMINISHING SIGNIFICANTLY IN WW. REMAINDER WW MAY BE CANCELED BEFORE SCHEDULED 5Z EXPIRATION OR ALLOWED TO EXPIRE AT THAT TIME. ACTIVITY STILL IN ERN-MOST COUNTIES OF WW NEAR IRK -- ALONG TAIL END OF MCS -- IS EXPECTED TO MOVE NEWD ACROSS NERN MO AND SERN IA WITH OCCASIONAL HAIL AND STRONG-SEVERE GUSTS POSSIBLE. REF SPC MESOSCALE DISCUSSION 520 FOR DETAILED DISCUSSION ON AREA E OF WW. MEANWHILE...INITIAL LINE OF FRONTALLY FORCED TSTMS OVER SERN KS MOSTLY HAS WEAKENED...EXCEPT FOR ISOLATED SEVERE TSTM LOCATED OVER VERNON COUNTY MO...AS OF 415Z. THIS TSTM HAS DISPLAYED INTERMITTENT SUPERCELL CHARACTERISTICS AND PRODUCED HAIL ESTIMATED UP TO 1.75 INCH DIAMETER...IN ENVIRONMENT OF STRONG LOW LEVEL SHEAR. 50-60 KT LLJ CONTRIBUTES TO 0-3 KM SRH EXCEEDING 700 J/KG OVER NARROW CORRIDOR AHEAD OF CONVECTIVE BAND. EFFECTIVE SHEARS BASED ON RUC SOUNDINGS HAVE WEAKENED CONSIDERABLY BASED ON STRONG SBCINH...ALTHOUGH SLGT MODIFICATIONS RESULT IN LIFTED PARCELS ROOTED NEAR/SLIGHTLY ABOVE SFC. CINH SHOULD CONTINUE TO LIMIT CONVECTIVE COVERAGE...BUT SRN/CENTRAL MO AREA WILL BE MONITORED FOR POSSIBLE WW. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...SGF...EAX... 37629456 38199386 38769341 39419286 40359221 40129083 37879094 WWWW From Mcd at goshenarc.org Sun Apr 16 12:17:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 08:17:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161215 SWOMCD SPC MCD 161215 KYZ000-INZ000-TNZ000-ILZ000-161415- MESOSCALE DISCUSSION 0523 NWS STORM PREDICTION CENTER NORMAN OK 0715 AM CDT SUN APR 16 2006 AREAS AFFECTED...EXTREME SERN IL...WRN KY AND SRN IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161215Z - 161415Z THUNDERSTORMS MOVING INTO WRN KY FROM EXTREME SERN IL MAY CONTINUE TO POSE A THREAT FOR ISOLATED MARGINALLY SEVERE HAIL NEXT COUPLE HOURS. THE THREAT DOES NOT APPEAR SUFFICIENT TO WARRANT A WW AT THIS TIME. EARLY THIS MORNING STORMS WERE DEVELOPING FROM EXTREME SRN IL INTO WRN KY AND SPREADING EWD. STORMS ARE ELEVATED AND ROOTED NEAR 700 MB BASED ON RUC SOUNDING DATA. STEEP MID LEVEL LAPSE RATES AROUND 8 C/KM AND EFFECTIVE CLOUD LAYER SHEAR SUPPORTIVE OF UPDRAFT ROTATION WILL SUPPORT HAIL WITH THE STRONGER STORMS. HOWEVER...MODEST MUCAPE AOB 800 J/KG SUGGESTS OVERALL HAIL SIZE SHOULD GENERALLY REMAIN 1 INCH OR LESS. FORCING FOR ASCENT ASSOCIATED WITH A WSWLY LOW LEVEL JET AND A VORTICITY LOBE ROTATING THROUGH BASE OF UPPER TROUGH WILL CONTINUE TO SUPPORT DEVELOPMENT OF STORMS THROUGH WRN KY AND INTO SRN IL NEXT COUPLE HOURS. ACTIVITY IS SUBSEQUENTLY EXPECTED TO BEGIN A WEAKENING TREND AS THE LOW LEVEL JET DIMINISHES LATER THIS MORNING. ..DIAL.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...IND...PAH... 36588898 37478899 38888697 38138575 36638738 WWWW From Mcd at goshenarc.org Sun Apr 16 16:00:22 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 12:00:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161558 SWOMCD SPC MCD 161557 WIZ000-ILZ000-MOZ000-IAZ000-MNZ000-161800- MESOSCALE DISCUSSION 0524 NWS STORM PREDICTION CENTER NORMAN OK 1057 AM CDT SUN APR 16 2006 AREAS AFFECTED...ERN IA....SRN WI...NWRN IL...NERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161557Z - 161800Z THREAT FOR HAIL PRODUCING THUNDERSTORMS WAS INCREASING ACROSS NERN IA...SWRN WI...AND PARTS OF NWRN IL LATE THIS MORNING. AREAS FROM SCNTRL/SERN IA...EAST/SOUTHEAST TO NERN MO/WRN IL MAY SEE AN INCREASE IN SURFACE-BASED STORMS NEXT FEW HOURS. WATCHES ARE POSSIBLE ACROSS PARTS OF THESE AREAS...PROBABLY WITHIN 1-2 HOURS. ARC OF CONVECTION WAS INCREASING IN COVERAGE AHEAD OF DEEP LAYER CYCLONE OVER IA THIS MORNING. THIS ACTIVITY WAS DEVELOPING TO THE NORTH OF THE SURFACE WARM FRONT AND EAST OF THE LOW WHERE STRONGER DYNAMIC FORCING ASSOCIATED WITH THE LARGE SCALE SYSTEM WAS BEGINNING TO OVERSPREAD LOW LEVEL WARM/MOIST CONVEYOR BELT. GIVEN LAPSE RATES EVIDENT ON MORNING SOUNDINGS FROM ILX AND DVN...EXPECT THESE STORMS TO PRODUCE SOME HAIL. WHILE THE CONVECTION CURRENTLY NORTH OF THE WARM FRONT WAS LIKELY ROOTED ABOVE CAPPED BOUNDARY LAYER...STORMS ARE EXPECTED TO ROOT INTO MOIST AND INCREASINGLY UNSTABLE AIR MASS NEAR SFC LOW...AND ESEWD FROM THE SFC LOW ALONG THE WARM FRONT...AND AHEAD OF WIND SHIFT/CONFLUENCE LINE MOVING EAST ACROSS NERN MO. DEEP LAYER VORTICITY AND LOW LEVEL CAPE DEVELOPING NEAR THE SFC LOW...AND STRONG LOW LEVEL SHEAR/HELICITY IN THE VICINITY OF THE WARM FRONT SHOULD SUPPORT ROTATING STORMS UPDRAFTS/SUPERCELLS. THIS ACTIVITY IS EXPECTED TO INTENSIFY AS GREATER WARM SECTOR DESTABILIZATION OCCURS INTO THE AFTERNOON. THE POTENTIAL FOR LARGE HAIL...AND AN INCREASING CHANCE OF DAMAGING WINDS/TORNADOES...SUGGEST WATCHES WILL BE NEEDED OVER PARTS OF THE REGION OVER THE NEXT FEW HOURS. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LOT...ILX...MKX...LSX...DVN...ARX...DMX...EAX... 40418903 40088919 39618979 39189043 38899092 38769157 38779239 39579231 40229269 40589308 40819363 41319379 41949377 42359353 43139284 43339243 43529131 43649024 43198864 42708843 41958854 40888894 WWWW From Mcd at goshenarc.org Sun Apr 16 18:10:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 14:10:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161808 SWOMCD SPC MCD 161808 INZ000-ILZ000-161945- MESOSCALE DISCUSSION 0525 NWS STORM PREDICTION CENTER NORMAN OK 0108 PM CDT SUN APR 16 2006 AREAS AFFECTED...EASTERN IL INTO CENTRAL/NORTHERN INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 161808Z - 161945Z A TORNADO WATCH APPEARS LIKELY BY 19Z-20Z ACROSS EASTERN IL INTO CENTRAL/NORTHERN INDIANA. THIS MAY INCLUDE AN UPGRADE OF THE NORTHEAST IL/NORTHWEST INDIANA PORTION OF SEVERE TSTM WATCH 194. WATER VAPOR IMAGERY/SURFACE ANALYSIS DEPICTS VERTICALLY STACKED LOW ACROSS SOUTH CENTRAL/SOUTHEAST IA...WITH WARM FRONT EXTENDING E/SE ACROSS CENTRAL IL INTO CENTRAL INDIANA...LARGELY PARALLEL WITH THE INTERSTATE 74 CORRIDOR. MODERATELY AGGRESSIVE DESTABILIZATION CONTINUES TO OCCUR IN PRESENCE OF AMPLE INSOLATION...WITH PROGRESSIVELY ACTIVE CU FIELD...ESPECIALLY NOTED IN BOTH SOUTH CENTRAL IL AND SOUTH CENTRAL INDIANA AT THIS TIME. ACCORDINGLY...OBJECTIVE ANALYSIS/ADJUSTED RUC SOUNDINGS SUGGESTS NEGLIGIBLE SURFACE BASED CINH FROM CENTRAL IL INTO CENTRAL INDIANA...WITH POTENTIAL FOR 1500 J/KG MLCAPE IN THE AMBIENT WARM SECTOR. MOST LIKELY SCENARIO IS FOR STRONG/SEVERE STORMS TO SPREAD EASTWARD OUT OF WESTERN IL INTO EASTERN IL/WESTERN INDIANA THROUGH MID/LATE AFTERNOON...ALTHOUGH IT REMAINS A DISTINCT POSSIBILITY FOR SOMEWHAT SEPARATE DEVELOPMENT IN VICINITY OF WARM FRONT THIS AFTERNOON. EITHER WAY...THREAT FOR SUPERCELLS CAPABLE OF VERY LARGE HAIL AND TORNADOES WILL STEADILY INCREASE REMAINDER OF THE AFTERNOON. TORNADO POTENTIAL WILL BE MAXIMIZED IN CORRIDOR ALONG/NORTH OF WARM FRONT FROM EAST CENTRAL IL INTO CENTRAL/NORTH CENTRAL INDIANA...WHERE BOUNDARY LAYER FLOW WILL TEND TO REMAIN BACKED WITH SUFFICIENTLY CURVED/ENLARGED LOW LEVEL HODOGRAPHS. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...IWX...IND...LOT...ILX... 41328829 41288645 40498518 39348489 38808620 38998790 40078855 WWWW From Mcd at goshenarc.org Sun Apr 16 18:21:05 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 14:21:05 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 161819 SWOMCD SPC MCD 161818 ILZ000-MOZ000-IAZ000-WIZ000-161915- MESOSCALE DISCUSSION 0526 NWS STORM PREDICTION CENTER NORMAN OK 0118 PM CDT SUN APR 16 2006 AREAS AFFECTED...SERN IA...NERN MO...WRN IL CONCERNING...TORNADO WATCH 193... VALID 161818Z - 161915Z SEVERE STORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY INSIDE OF TORNADO WATCH 193 OVER THE NEXT HOUR. LATEST ANALYSIS PLACES OCCLUDED LOW OVER SCNTRL IA WITH WARM FRONT EXTENDING EAST INTO NRN IL AND WIND SHIFT/CONFLUENCE AXIS DEVELOPING EAST INTO WRN IL. STRONGLY DIFFLUENT MID LEVEL FLOW AHEAD OF THE DEEP LAYER CYCLONE WAS ACTING ON DESTABILIZING WARM SECTOR AIR MASS FROM SERN IA ACROSS CNTRL IL AND SUPPORTING INCREASING TSTM DEVELOPMENT OVER THESE AREAS. DEEP LAYER SHEAR OF 40-50KT ACROSS IL PORTIONS OF THE WATCH IS MORE THAN ADEQUATE FOR SUPERCELLS AND EXPECT STORMS NOW DEVELOPING ACROSS CNTRL IL TO REACH SEVERE LEVELS SHORTLY. LARGE HAIL APPEARS TO BE THE MAIN THREAT FROM THIS CONVECTION. HOWEVER...STORMS NEAR OR CROSSING THE WARM FRONT...FROM GBG TO PIA...WILL NEED TO BE MONITORED FOR LOW LEVEL ROTATION AND POSSIBLE TORNADO THREAT GIVEN EFFECTIVE HELICITY VALUES 150-200 MS/S2 BASED ON CELL WSW MOTION AT 25KT. STORMS NEAR THE LOW AND EAST TO DVN AREA WERE DEVELOPING IN A WEAKER SHEAR ENVIRONMENT DUE TO WEAKER FLOW NEAR THE LOW CENTER. THIS IS FURTHER SUPPORTED BY LATEST DVN SOUNDING. HOWEVER...DVN SOUNDING ALSO DEPICTS SUFFICIENT LOW LEVEL CAPE FOR MODEST UPDRAFT STRETCHING. GIVEN STRONG BACKGROUND VORTICITY IN VICINITY OF THE LOW...A FEW OF THESE CELLS COULD ACQUIRE ROTATION AND POSE A HAIL AND BRIEF TORNADO THREAT INTO THIS AFTERNOON. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...LOT...ILX...LSX...DVN...ARX...DMX...EAX... 42609347 42629064 40488850 38418828 38169132 40539246 40569349 42149407 42189356 WWWW From Mcd at goshenarc.org Sun Apr 16 20:13:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:13:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162011 SWOMCD SPC MCD 162010 VAZ000-WVZ000-162145- MESOSCALE DISCUSSION 0527 NWS STORM PREDICTION CENTER NORMAN OK 0310 PM CDT SUN APR 16 2006 AREAS AFFECTED...SRN WV...WRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 162010Z - 162145Z A COUPLE OF SEVERE THUNDERSTORMS APPEAR POSSIBLE ACROSS PORTIONS OF WV AND WRN VA OVER THE NEXT HOUR OR SO. ANTICIPATED SEVERE POTENTIAL IN TERMS OF AREAL COVERAGE AND DURATION DOES NOT CURRENTLY APPEAR GREAT ENOUGH TO WARRANT A WATCH IN THIS AREA. ISOLATED STORMS HAVE INITIATED NEAR STATIONARY FRONT CROSSING THE CNTRL APPALACHIANS FROM WRN VA INTO SERN WV. DEVELOPMENT OF THIS ACTIVITY WAS BEING AIDED BY APPROACH OF WEAK SHORT WAVE TROUGH...UPSLOPE COMPONENT OF THE LOW LEVEL FLOW...AND DIURNAL DESTABILIZATION. LATEST DIAGNOSTIC DATA SUGGESTS THAT SHEAR AND INSTABILITY ACROSS THE REGION SHOULD SUPPORT A COUPLE OF ORGANIZED STORMS WITH SOME CHANCE FOR HAIL AND ISOLATED DAMAGING WINDS. HOWEVER...WEAK LARGE SCALE FORCING FOR ASCENT...AND DIURNAL NATURE OF THE INSTABILITY...WOULD SUGGEST THAT SEVERE THREAT SHOULD REMAIN LIMITED IN TIME AND SPACE. THERE IS SOME INDICATION IN LATEST GUIDANCE THAT STORM COVERAGE MAY INCREASE ACROSS PARTS OF THE REGION LATER THIS EVENING AS STRONGER FORCING DEVELOPS EWD FROM THE OH VALLEY. A WATCH IS NOT BEING PLANNED AT PRESENT. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX... 37107906 37028122 37288184 37598172 37778072 37877931 37687898 WWWW From Mcd at goshenarc.org Sun Apr 16 20:26:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:26:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162024 SWOMCD SPC MCD 162024 KYZ000-INZ000-ILZ000-MOZ000-162230- MESOSCALE DISCUSSION 0528 NWS STORM PREDICTION CENTER NORMAN OK 0324 PM CDT SUN APR 16 2006 AREAS AFFECTED...SOUTHEAST MO/SOUTHERN IL/WESTERN KY/SOUTHWEST INDIANA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 162024Z - 162230Z CLOSELY MONITORING DEVELOPMENTAL TRENDS ACROSS FAR SOUTHEAST MO/SOUTHERN IL INTO WESTERN KY/SOUTHWEST INDIANA FOR POSSIBILITY OF A WATCH ISSUANCE. ON SOUTHERN PERIPHERY OF TORNADO WATCH 193...MODERATE CU FIELD EXISTS INVOF SURFACE TROUGH ACROSS FAR SOUTHEAST MO/FAR SOUTHWEST IL...NAMELY FROM THE ST LOUIS METRO TO NEAR FARMINGTON MO AND POPLAR BLUFF MO. GIVEN RELATIVELY MORE MODEST MASS CONVERGENCE WITH SOUTHWARD EXTENT IN WARM SECTOR...LIKELIHOOD/EXTENT OF CONVECTIVE INITIATION IS QUESTIONABLE PROGRESSIVELY SOUTH. WHILE DETERMINISTIC/ENSEMBLE MODEL GUIDANCE ARE RATHER SCANT WITH CONVECTIVE DEVELOPMENT THIS AFTERNOON...LITTLE OR NO CONVECTIVE INHIBITION EXISTS PER RUC SOUNDINGS...WITH REGION BEING BRUSHED BY IA CLOSED LOW. WILL CONTINUE TO CLOSELY MONITOR DEVELOPMENT TRENDS OVER THE NEXT SEVERAL HOURS...AS MLCAPE OF 750-1000 J/KG AND STRONG VERTICAL SHEAR WOULD FAVOR A SUPERCELL AND LARGE HAIL/TORNADO THREAT GIVEN DEEP CONVECTION. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...LSX...SGF... 38329094 38398830 38528634 37448582 36908687 36698847 36748927 36849060 36969127 37519153 WWWW From Mcd at goshenarc.org Sun Apr 16 20:45:23 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:45:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162043 SWOMCD SPC MCD 162043 INZ000-ILZ000-MOZ000-IAZ000-162215- MESOSCALE DISCUSSION 0529 NWS STORM PREDICTION CENTER NORMAN OK 0343 PM CDT SUN APR 16 2006 AREAS AFFECTED...ERN IA...IL...IND CONCERNING...TORNADO WATCH 193...195... VALID 162043Z - 162215Z SEVERE WEATHER THREAT WILL CONTINUE TO DEVELOP EAST ACROSS ERN IL AND INTO WRN IND OVER THE NEXT FEW HOURS AS OCCLUDED SURFACE LOW REDEVELOPS EWD ALONG WARM FRONT OVER THESE AREAS. AN ARC OF SEVERAL INTENSE SUPERCELLS HAS DEVELOPED OVER THE PAST COUPLE OF HOURS ACROSS THE WARM SECTOR FROM SCNTRL TO CNTRL IL. NEW DEVELOPMENT WAS ALSO OCCURRING WEST OF THE INITIAL BAND OF STORMS...ACROSS LINCOLN...WRN STANFORD..AND EL PASO COUNTIES... INDICATING STRONG ASCENT WAS STILL OCCURRING ACROSS THIS REGION. FORCING AND DEEP SHEAR ACROSS THE REGION WILL CONTINUE TO SUPPORT SUPERCELLS WITH LARGE HAIL. DISCRETE CELLS MOVING INTO BACKED SURFACE FLOW OVER ERN IL WILL CONTINUE TO ENCOUNTER SUFFICIENT LOW LEVEL SHEAR FOR TORNADOES. EVENTUALLY...CELL MERGERS MAY SUPPORT THE EVOLUTION INTO A LARGER SCALE CONVECTIVE COMPLEX. ..CARBIN.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILN...LMK...IWX...IND...PAH...LOT...ILX...LSX...DVN...DMX... 38818533 38528687 38588843 38509026 39609011 40769109 40709218 40619248 41289236 42189222 42109030 41578886 41248816 41058560 WWWW From Mcd at goshenarc.org Sun Apr 16 20:52:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 16:52:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162051 SWOMCD SPC MCD 162050 INZ000-MIZ000-ILZ000-WIZ000-162215- MESOSCALE DISCUSSION 0530 NWS STORM PREDICTION CENTER NORMAN OK 0350 PM CDT SUN APR 16 2006 AREAS AFFECTED...NORTH CENTRAL/NORTHEAST IL AND FAR SOUTHERN WI/FAR NORTHERN INDIANA CONCERNING...SEVERE THUNDERSTORM WATCH 194... VALID 162050Z - 162215Z VALID PORTION OF SEVERE THUNDERSTORM WATCH 194 CONTINUES UNTIL 00Z...WITH PRIMARY HAZARD OF LARGE HAIL. WELL NORTH OF WARM FRONT ACROSS CENTRAL IL/CENTRAL INDIANA...PRIMARY THREAT FOR LARGE HAIL CONTINUES THROUGH LATE AFTERNOON ACROSS NORTH CENTRAL/NORTHEAST IL INTO FAR SOUTHERN WI/FAR NORTHERN INDIANA. AHEAD OF STACKED LOW OVER SOUTHEAST IA...AMPLE ELEVATED INSTABILITY ABOVE COOL BOUNDARY LAYER WILL CONTINUE TO SUPPORT UPDRAFTS CAPABLE OF LARGE HAIL...WITH MUCAPE UP TO 1000 J/KG ACROSS MUCH OF WW 194 PER RUC SOUNDINGS. HOWEVER...MODEST EFFECTIVE BULK SHEAR AND TENDENCY FOR STORMS TO CLUSTER MAY TEMPER VIGOROUS DEVELOPMENT...ESPECIALLY WITH NORTH/NORTHWEST EXTENT ACROSS WW 194. ..GUYER.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...IWX...LOT...MKX...DVN... 42629006 42708828 41678640 41328647 41458771 41618906 41818960 WWWW From Mcd at goshenarc.org Sun Apr 16 23:16:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 19:16:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 162314 SWOMCD SPC MCD 162314 INZ000-ILZ000-170115- MESOSCALE DISCUSSION 0531 NWS STORM PREDICTION CENTER NORMAN OK 0614 PM CDT SUN APR 16 2006 AREAS AFFECTED...PORTIONS INDIANA...SRN/ERN IL. CONCERNING...TORNADO WATCH 193...195... VALID 162314Z - 170115Z SEVERE POTENTIAL CONTINUES TO SHIFT EWD FROM ERN IL INTO WRN INDIANA...IN ASSOCIATED WITH LARGE COMPLEX OF TSTMS THAT INCLUDES SEVERAL SUPERCELLS. SRN-MOST OF THIS ACTIVITY -- WITH UNIMPEDED SFC-BASED INFLOW ATTM -- IS STRONGLY RIGHTWARD DEVIANT...CLASSIC/CYCLIC SUPERCELL OVER CRAWFORD COUNTY IL WITH HISTORY OF FUNNEL CLOUDS AND AT LEAST TWO TORNADO REPORTS. THIS TSTM SHOULD MOVE ACROSS WABASH RIVER OVER PORTIONS SULLIVAN/KNOX/DAVIESS/GREENE COUNTIES INDIANA THROUGH 2Z. LARGE HAIL AND TORNADO POTENTIAL ALSO WILL CONTINUE FOR AT LEAST ANOTHER COUPLE HOURS WITH ACTIVITY FARTHER N...MOVING EWD ACROSS IL/INDIANA BORDER. SFC MESOANALYSIS SHOWS OCCLUDED LOW OVER ERN IA...TRIPLE-POINT LOW BETWEEN SPI-PIA...SYNOPTIC WARM FRONT ESEWD FROM LATTER LOW ACROSS IND TO CINCINNATI AREA. MOST CONVECTION SHOULD REMAIN ALONG AND E OF SECONDARY WARM FRONTAL ZONE -- A DIFFERENTIAL HEATING BOUNDARY SEPARATING MORE STRONGLY MIXED BOUNDARY LAYER AIR OF SERN MO/SWRN IL FROM AREAS FORMERLY COVERED IN STRATUS CLOUDS OVER SERN IN/SWRN INDIANA. THIS BOUNDARY -- INITIALLY ANALYZED FROM NEAR SPI TO 20 W EVV -- SHOULD MOVE EWD OUT OF SERN PORTIONS WW 193 SHORTLY. THROUGH 2Z...AIR MASS BETWEEN WARM FRONTS WILL MAINTAIN RELATIVELY LOW LCL...INFLOW-LAYER PARCELS THAT ARE SFC-BASED OR VERY NEARLY SO...AND SOMEWHAT BACKED BOUNDARY LAYER FLOW IN REGION OF LOCALLY MAXIMIZED PRESSURE FALLS. ACCORDINGLY...0-1 KM SRN IS MAXIMIZED OVER SERN IL/SWRN INDIANA AT 250-300 J/KG...WITH EFFECTIVE SHEARS 40-50 KT AND MLCAPES 1000-1500 J/KG. ..EDWARDS.. 04/16/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IWX...IND...PAH...LOT...ILX...LSX...DVN... 38488863 39798907 40768978 41188934 41078793 40918695 40898597 40688561 40118542 39388543 38868558 38578679 WWWW From Mcd at goshenarc.org Mon Apr 17 01:10:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 16 Apr 2006 21:10:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 170109 SWOMCD SPC MCD 170108 INZ000-KYZ000-ILZ000-170245- MESOSCALE DISCUSSION 0532 NWS STORM PREDICTION CENTER NORMAN OK 0808 PM CDT SUN APR 16 2006 AREAS AFFECTED...EXTREME SRN INDIANA//EXTREME N-CENTRAL KY. CONCERNING...HEAVY RAINFALL...TORNADO WATCH 195... VALID 170108Z - 170245Z NARROW CORRIDOR OF SRN INDIANA BETWEEN SRN EDGE OF WW 195 AND OH RIVER WILL BE MONITORED FOR SEVERE POTENTIAL ALONG SRN EDGE OF SEVERE COMPLEX OF TSTMS -- NOW MOVING FROM ERN IL INTO WRN INDIANA. PRIMARY AREA OF CONCERN IS ASSOCIATED WITH HYBRID HP SUPERCELL/BOW ECHO OVER KNOX COUNTY INDIANA...WHICH PRODUCED MEASURED HURRICANE-FORCE GUSTS AND WIND DAMAGE IN ERN CRAWFORD COUNTY IL. THIS ACTIVITY MAY SURVIVE LONG ENOUGH TO MOVE OUT OF SRN-MOST COUNTIES IN WW...AND ACROSS PORTIONS ORANGE/WASHINGTON COUNTIES...TOWARD NWRN/NRN FRINGES SDF METRO AREA. MODIFIED RUC SOUNDINGS INDICATE SIGNIFICANT INCREASE IN SBCINH WITH SWD EXTENT ACROSS SWRN/S-CENTRAL INDIANA INTO ADJACENT PORTION NRN KY. BOUNDARY LAYER ALSO IS EXPECTED TO DESTABILIZE GRADUALLY OVER NEXT FEW HOURS BECAUSE OF DIABATIC SFC COOLING. THEREFORE THERE IS CONSIDERABLE PROBABILITY THAT TSTMS MAY NOT SURVIVE AS FAR AS SDF AREA. HOWEVER...SOME POTENTIAL EXISTS FOR STRONG CONVECTIVE-SCALE LIFT TO SUSTAIN THIS ACTIVITY -- SUCH AS STRONG FORCED ASCENT PROVIDED BY LEADING EDGE OF OUTFLOW SLAB. VERTICAL SHEAR PROFILES WILL REMAIN AT LEAST MARGINALLY FAVORABLE...MAINLY IN TERMS OF BOUNDARY LAYER SRH BECAUSE OF STRONG TURNING WITH HEIGHT IN LOW LEVELS. ADDITIONALLY...EXPECT TRAINING OF CORES PRODUCING 2-3 INCH/HOUR RAINFALL RATES ALONG SWRN INDIANA CORRIDOR BETWEEN KNOX/SULLIVAN COUNTIES...BMG AREA AND ORANGE COUNTY. ..EDWARDS.. 04/17/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...ILX... 38708827 39008773 39448712 39498654 39418582 39048557 38598560 38298563 38198579 38118627 38348757 WWWW From Mcd at goshenarc.org Mon Apr 17 04:45:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 00:45:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 170443 SWOMCD SPC MCD 170443 NDZ000-MTZ000-170645- MESOSCALE DISCUSSION 0533 NWS STORM PREDICTION CENTER NORMAN OK 1143 PM CDT SUN APR 16 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/NERN MT...EXTREME NWRN ND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 170443Z - 170645Z BAND OF TSTMS -- NOW MOVING NNEWD NEARLY 40 KT ACROSS SRN MCCONE COUNTY -- SHOULD MOVE TOWARD PORTIONS RICHLAND/ROOSEVELT/DANIELS COUNTIES DURING NEXT 2-3 HOURS. THIS ACTIVITY ALSO MAY BUILD/PROPAGATE NEWD INTO ZONE OF FAVORABLE ELEVATED WAA...AND MAY CLIP NWRN CORNER OF ND. THOUGH INFLOW LAYER APPEARS TO BE ELEVATED WELL AGL...SOME OF THIS ACTIVITY MAY PRODUCE DAMAGING SFC GUSTS AS WELL AS HAIL. WW NOT ANTICIPATED GIVEN LIMITED AREA AND TIME OF SEVERE POTENTIAL. VWP DATA AND MODEL SOUNDINGS INDICATE STRONG VEERING WITH HEIGHT AND LOW LEVEL WAA PROFILE ACROSS THIS REGION...WITH MOISTENING IN 650-800 MB LAYER WHERE EFFECTIVE INFLOW IS ESTIMATED. ELEVATED MUCAPES UP TO ABOUT 500 J/KG ARE EXPECTED TO CONTINUE JUST AHEAD OF THIS CONVECTION. THOUGH CONVECTIVELY STABLE...AIR MASS FROM SFC-800 MB ALSO IS RELATIVELY DRY AND SUPPORTS DCAPE VALUES COMPARABLE TO LARGEST MUCAPES...BASED ON MODIFIED RUC SOUNDINGS. GIVEN THAT FACTOR AND SHAPE OF WET BULB PROFILE IN SUBCLOUD LAYER. ISOLATED 58 KT GUST WAS REPORTED IN ROSEBUD COUNTY FROM THIS ACTIVITY...AND OCNL DAMAGING GUSTS MAY CONTINUE TO PENETRATE BOUNDARY LAYER AND REACH SFC. ..EDWARDS.. 04/17/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...GGW... 47220543 47440581 47530615 47580630 48990574 48980347 47290517 WWWW From Mcd at goshenarc.org Tue Apr 18 00:36:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 20:36:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 180033 SWOMCD SPC MCD 180033 NDZ000-SDZ000-MTZ000-WYZ000-180200- MESOSCALE DISCUSSION 0540 NWS STORM PREDICTION CENTER NORMAN OK 0733 PM CDT MON APR 17 2006 AREAS AFFECTED...PORTIONS EXTREME NERN WY...WRN SD...SWRN ND CONCERNING...SEVERE THUNDERSTORM WATCH 198... VALID 180033Z - 180200Z BAND OF SEVERE TSTMS WILL MOVE NEWD FROM HARDING COUNTY SD INTO BOWMAN COUNTY ND WITHIN NEXT HOUR...WITH POTENTIAL FOR SEVERE HAIL/GUSTS. ADDITIONAL/ISOLATED TSTMS ARE MOVING NWD INTO SRN HARDING COUNTY AND DEVELOPING FARTHER SW INVOF SD/WY BORDER. MIDLEVEL CONVECTION OVER ERN WY IS ASSOCIATED WITH BAND OF ENHANCED LARGE SCALE ASCENT MOVING EWD AHEAD OF INTENSE NRN ROCKIES/NRN GREAT BASIN TROUGH ALOFT. THIS ACTIVITY IS CHARACTERIZED BY INCREASING CG LIGHTNING...BUILDING REFLECTIVITIES...AND COOLING IR CLOUD TOPS. BOUNDARY LAYER ACROSS SRN PORTIONS WW...AND REMAINDER SWRN SD...REMAINS RELATIVELY DRY WITH SFC DEW POINTS MID 40S ON PLAINS AND 30S IN BLACK HILLS. HOWEVER...MOIST ADVECTION AND STRENGTHENING LLJ MAY RESULT IN SOME OF THIS ACTIVITY BECOMING ROOTED NEAR SFC. MODIFIED 00Z RAP RAOB AND RUC SOUNDINGS INDICATE WELL MIXED SUBCLOUD LAYER CONDUCIVE TO MAINTAINING SEVERE DOWNDRAFTS AND HAIL TO SFC...IN FAVORABLE VERTICAL SHEAR PROFILES FOR BOTH SUPERCELLS AND BOW FORMATIONS. 53 KT GUST AND THREE REPORTS OF .75-1.75 INCH HAIL HAVE BEEN RECEIVED COMBINED AS OF 0030Z...OVER HARDING/BOWMAN COUNTIES. THIS REPRESENTS STRONG CLIMATOLOGICAL ANOMALY. SPC SEVERE DATABASE INDICATES THESE ARE FIRST RECORDED APRIL SEVERE EVENTS IN THEIR COUNTIES...AND HALF THE TOTAL OF EIGHT APRIL REPORTS FOR ALL COUNTIES IN WW...SINCE RECORDS BEGAN IN 1950. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...UNR...BYZ... 44160252 44180435 47050357 47060168 WWWW From Mcd at goshenarc.org Tue Apr 18 03:27:25 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 17 Apr 2006 23:27:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 180325 SWOMCD SPC MCD 180325 SDZ000-180500- MESOSCALE DISCUSSION 0541 NWS STORM PREDICTION CENTER NORMAN OK 1025 PM CDT MON APR 17 2006 AREAS AFFECTED...PORTIONS WRN SD. CONCERNING...SEVERE THUNDERSTORM WATCH 198... VALID 180325Z - 180500Z SEVERE TSTM POTENTIAL IS EXPECTED TO DIMINISH THROUGH REMAINDER EVENING ACROSS WW AREA...THOUGH ISOLATED HAIL/GUSTS NEAR SEVERE LEVELS MAY STILL OCCUR PARTICULARLY OVER ERN HALF OF ORIGINAL WW...SWD ACROSS PENNINGTON COUNTY PLAINS TO NEAR NEB BORDER. ND ALREADY HAS BEEN REMOVED FROM WW AND REMAINING PORTIONS IN SD PORTION MAY BE ALLOWED TO EXPIRE AS SCHEDULED. MERIDIONAL BAND OF TSTMS WILL CONTINUE SHIFTING EWD ACROSS THIS REGION...WHILE EMBEDDED CELLS AND LINE SEGMENTS MOVE NNEWD 30-40 KT. ONE SUCH BAND IS EVIDENT ATTM OVER ERN CUSTER/NWRN SHANNON COUNTY...HEADED FOR CENTRAL/ERN PORTIONS OF BOTH PENNINGTON AND MEADE COUNTIES. PRONOUNCED OUTFLOW BOUNDARY HAS SURGED WELL E OF CONVECTIVE BAND...FURTHER STABILIZING NEAR-SFC LAYER BEYOND AMBIENT DIABATIC COOLING RATES. STILL...MODIFIED RAOBS AND RUC SOUNDINGS SHOW LARGE SUBCLOUD DEW POINT DEPRESSIONS ABOVE STABLE OUTFLOW LAYER -- REMNANTS OF EARLIER/DEEPLY-MIXED BOUNDARY LAYER AIR MASS. THIS MAY SUPPORT POTENTIAL FOR ISOLATED DAMAGING GUSTS TO REACH SFC...AS WELL AS LARGE HAIL...FROM MOST VIGOROUS CONVECTION. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ABR...UNR... 44200367 45930322 45920195 43020210 43000333 WWWW From Mcd at goshenarc.org Tue Apr 18 17:33:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 13:33:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 181731 SWOMCD SPC MCD 181730 FLZ000-GAZ000-ALZ000-181930- MESOSCALE DISCUSSION 0542 NWS STORM PREDICTION CENTER NORMAN OK 1230 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS OF ERN AL...SWRN GA AND THE FLA PANHANDLE CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 181730Z - 181930Z ISOLATED SVR TSTMS MAY OCCUR ALONG A STATIONARY BOUNDARY EXTENDING FROM ECENTRAL AL SWD INTO SWRN GA AND ERN FLA PANHANDLE BY 20Z. AREA WILL BE MONITORED FOR A POSSIBLE WW. 17Z VIS SAT IMAGERY SHOWS TOWERING CU ALONG A BOUNDARY THAT EXTENDED ROUGHLY FROM 25 E BHM TO 40 W ABY TO 15 E TLH. DESPITE VERY WEAK TO MINIMAL CINH REMAINING PER MODIFIED 12Z BMX AND RECENT RUC SOUNDINGS...WEAK CONVERGENCE HAS AS YET PREVENTED TSTM DEVELOPMENT. THE GREATEST PROBABILITY FOR INITIAL TSTM DEVELOPMENT IS OVER THE FAR SWRN GA/ERN FLA PANHANDLE WHERE CONVERGENCE WAS SLIGHTLY GREATER AS ANOTHER BOUNDARY MOVES WWD ACROSS THE AREA AND INTERSECTS THE INITIAL STATIONARY BOUNDARY. REGARDLESS...GIVEN CONTINUED DAYTIME HEATING AND DESTABILIZATION AT LEAST ISOLATED TSTM DEVELOPMENT IS EXPECTED ALONG THE MAIN STATIONARY BOUNDARY BY 20Z. ALTHOUGH 1-4 KM FLOW REMAINS RATHER WEAK PER RECENT VWP DATA...MODERATE NWLY 4-9 KM FLOW /STRONGEST ABOVE 6 KM/ MAY BE SUFFICIENTLY STRONG TO FAVOR STORM TOP VENTILATION. COMBINED WITH WEAK ELY FLOW ON THE EAST SIDE OF THE STATIONARY BOUNDARY...SOME STORM ROTATION APPEARS LIKELY. ALTHOUGH LAPSE RATES INITIALLY ARE RELATIVELY POOR /6-6.5 DEG C/KM / SLIGHT MID LVL COOLING SHOULD AID IN STEEPENING LAPSE RATES THROUGH THE AFTERNOON. WITH MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG / MARGINALLY SVR HAIL WILL BE POSSIBLE. ADDITIONALLY...STEEP LOW LEVEL LAPSE RATES /25 DEG T/TD SPREADS AT THE SFC/ MAY SUPPORT DMGG WIND GUSTS AS WELL. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...MOB... 31648422 32898534 33738608 33638653 32648656 31368589 30558533 30268476 30178385 30678348 WWWW From Mcd at goshenarc.org Tue Apr 18 20:07:53 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 16:07:53 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182005 SWOMCD SPC MCD 182005 TXZ000-182200- MESOSCALE DISCUSSION 0544 NWS STORM PREDICTION CENTER NORMAN OK 0305 PM CDT TUE APR 18 2006 AREAS AFFECTED...TX HILL COUNTRY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182005Z - 182200Z ISOLATED SVR TSTMS MAY DEVELOP BY 22Z OVER THE WRN PORTIONS OF THE TX HILL COUNTRY FROM EDWARDS COUNTY NEWD TOWARDS LLANO COUNTY. GIVEN THE MARGINAL NATURE OF THE THREAT EXPECTED...A WW IS NOT ANTICIPATED ATTM. LATEST VISIBLE SAT IMAGERY SHOWS TOWERING CU ALONG A DRYLINE FROM EDWARDS COUNTY NEWD INTO MASON COUNTY. TEMPERATURES HAVE WARMED INTO THE MID-UPPER 90S ACROSS THE HILL COUNTRY WITH DEWPTS IN THE 50S. DESPITE THE LOW DEWPTS...MODERATE INSTABILITY WAS REALIZED WITH MLCAPES AROUND 1500 J/KG. ENOUGH CINH REMAINS AT 19Z /75-100 J/KG / THAT TSTM DEVELOPMENT WILL LIKELY TAKE A FEW MORE HRS TO OCCUR. DESPITE THE WEAK LOW LEVEL CONVERGENCE...A SUBTLE MID LEVEL WAVE SEEN ON WV IMAGERY OVER NRN MX MAY SUPPORT SOME LARGE SCALE LIFT. A DEEP MIXED LAYER BENEATH MODERATE INSTABILITY /DCAPES AROUND 1500 J/KG / AND STEEP LAPSE RATES UP TO 10 KFT MAY SUPPORT DMGG WIND GUSTS WITH THE STRONGEST TSTMS. DESPITE STEEP MID LEVEL LAPSE RATES AND MODERATE MID LEVEL SHEAR...VERY WARM TEMPERATURES IN THE LOW LEVELS WILL LIKELY KEEP ANY HAIL TO MARGINAL LVLS. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX...SJT... 30729879 30459974 30180006 29770031 29450018 29209966 29299940 29539866 29959808 30579800 30879820 WWWW From Mcd at goshenarc.org Tue Apr 18 21:08:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 17:08:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182106 SWOMCD SPC MCD 182106 ALZ000-TNZ000-182300- MESOSCALE DISCUSSION 0545 NWS STORM PREDICTION CENTER NORMAN OK 0406 PM CDT TUE APR 18 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182106Z - 182300Z ISOLATED SVR TSTMS WILL BE POSSIBLE ALONG A STATIONARY BOUNDARY ACROSS NRN AL NWD INTO SRN MIDDLE TN. AREA WILL BE MONITORED FOR A POSSIBLE WW. DESPITE UPPER LEVEL RIDGING...ISOLATED CONVECTION HAS DEVELOPED OVER NRN AL ALONG STATIONARY SFC BOUNDARY. ALTHOUGH LOW LEVEL FLOW WAS RELATIVELY WEAK...MID LEVEL NWLY FLOW FROM 30-40 KTS AND MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG/ ARE FAVORABLE FOR AT LEAST AN ISOLATED SVR THREAT. DEGREE OF ADDITIONAL INITIATION REMAINS UNCERTAIN GIVEN LACK OF SAT DATA AND WEAK SYNOPTIC-MESOSCALE FORCING. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN... 34828572 36028710 35768768 35358781 34528761 33818659 33508595 33738550 33878549 WWWW From Mcd at goshenarc.org Tue Apr 18 22:48:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 18:48:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182246 SWOMCD SPC MCD 182245 MOZ000-190045- MESOSCALE DISCUSSION 0546 NWS STORM PREDICTION CENTER NORMAN OK 0545 PM CDT TUE APR 18 2006 AREAS AFFECTED...MO. CONCERNING...TORNADO WATCH 199... VALID 182245Z - 190045Z DEEP CB DEVELOPMENT NOW EVIDENT OVER NWRN AND SWRN PORTIONS WW...SPECIFICALLY FROM SZL AREA NWWD TOWARD GENTRY COUNTY. ADDITIONAL TOWERS ARE EVIDENT ON VIS IMAGERY OVER HICKORY COUNTY. EXPECT CONVECTION TO FILL IN BETWEEN THESE AREAS DURING NEXT 1-2 HOURS. OPTIMAL COMBINATION OF BUOYANCY AND SHEAR APPEARS TO BE IN AIR MASS BETWEEN MKC-COU...SEWD ACROSS CENTRAL MO. TSTMS FARTHER NW MAY DEVELOP SUPERCELL CHARACTERISTICS BUT WILL LIFT NEWD OVER RELATIVELY STABLE AIR MASS NEAR IA/MO BORDER. 22Z SFC MESOANALYSIS SHOWS OCCLUDED FRONT FROM NWRN CORNER IA SSEWD OVER CLINTON/RAY COUNTIES MO...WHERE WARM/COLD FRONTAL OCCLUSION IS PROPAGATING SEWD ATTM. COLD FRONT EXTENDS SWWD TO VICINITY JLN AND SHOULD CONTINUE MOVING EWD 15-20 KT. WARM FRONT -- ANALYZED FROM RAY COUNTY SEWD PAST VIH TO VICINITY WRN TIP OF KY...LIFTING NEWD APPROXIMATELY 10 KT. WEAK MESOLOW IS EVIDENT INVOF SZL..ALONG CONFLUENCE LINE THAT IS ANALYZED FROM NEAR OCCLUSION POINT SSEWD TO NEAR SGF. OCCLUDED/COLD FRONTS AND CONFLUENCE LINE ALSO ARE EVIDENT IN EAX REFLECTIVITY LOOPS AS FINE LINES. PRIMARY AREAS OF DEVELOPMENT SHOULD REMAIN ALONG OCCLUDED FRONT N OF I-70. FARTHER S...ACTIVITY SHOULD FORM MAINLY ALONG CONFLUENCE LINE...PARTICULARLY AS COLD FRONT MERGES AND ENHANCES BOUNDARY LAYER CONVERGENCE. VERTICAL SHEAR PROFILES WILL BE FAVORABLE E OF CONFLUENCE LINE WHERE SLY/SSELY FLOW IS PRESENT...AND EVEN MORE FAVORABLE ALONG WARM FRONT. ACCORDINGLY...0-3 KM SRH RANGES FROM LESS THAN 100 J/KG BETWEEN COLD FRONT AND CONFLUENCE LINE TO 200-300 J/KG ALONG AND E OF WARM FRONT...WHERE DEEP-LAYER SHEAR ALSO IS MAXIMIZED. MODIFIED 21Z SGF RAOB AND RUC SOUNDINGS SHOW STEEP MIDLEVEL LAPSE RATES OF 8-9 DEG C/KM SUPPORTING MLCAPES 3000-3500 J/KG...NEAR AND SE OF MESOLOW. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...DVN...SGF...EAX... 37539110 37549365 40549488 40539224 WWWW From Mcd at goshenarc.org Tue Apr 18 23:17:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:17:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182315 SWOMCD SPC MCD 182314 ARZ000-LAZ000-TXZ000-OKZ000-190115- MESOSCALE DISCUSSION 0547 NWS STORM PREDICTION CENTER NORMAN OK 0614 PM CDT TUE APR 18 2006 AREAS AFFECTED...FAR SERN OK...NERN TX...SWRN AR AND NWRN LA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182314Z - 190115Z NON-SURFACE BASED CONVECTION HAS DEVELOPED RECENTLY OVER NERN TX BENEATH HIGH CLOUD COVER. IT IS UNCERTAIN ATTM WHETHER CONVECTION CAN BECOME SURFACE BASED IN THE NEXT HR OR TWO BEFORE INCREASING BOUNDARY LAYER INHIBITION OCCURS. AREA WILL BE MONITORED FOR A POSSIBLE WW. RECENT SFC OBS FROM DFW HAD BKN150 AND WEBCAMS IN THE DFW AREA SUGGEST THAT A MID LEVEL ACCAS BAND WITH SOME VIRGA WAS MOVING ACROSS THE REGION IN ASSOCIATION WITH MID/HIGH LEVEL SPEED MAX. SUFFICIENT MID LEVEL MOISTENING HAS LIKELY OCCURRED WITH THIS VIRGA/ACCAS TO ALLOW FOR ELEVATED CONVECTION TO DEVELOP OVER NERN TX. SURFACE OBSERVATIONS OVER THE ARKLATEX REGION AHEAD OF THIS CONVECTION...MODIFIED FOR 21Z RUC FORECAST SOUNDINGS...SUGGEST THAT AROUND 100 J/KG OF MLCINH REMAINS. GIVEN RECENT OBSERVED CELL MOTION ON RADAR...IT APPEARS CONVECTION REMAINS NON-SURFACE BASED. THIS BEING SAID...IT REMAINS POSSIBLE THAT SUFFICIENT EVAPORATIVE COOLING MIGHT OCCUR IN THE NEXT HR OR TWO /WHILE THE BOUNDARY LAYER HAS THE LEAST CINH/ THAT THIS CONVECTION COULD STILL BECOME SURFACE BASED. MODERATE INSTABILITY /MLCAPES AROUND 2000 J/KG / AND SUFFICIENT SHEAR WILL ALLOW FOR A SVR WIND/HAIL THREAT IF STORMS DO BECOME SURFACE BASED. ..CROSBIE.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...FWD... 33999438 33519537 32949517 32589459 32469384 32969293 33899262 WWWW From Mcd at goshenarc.org Tue Apr 18 23:30:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:30:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182328 SWOMCD SPC MCD 182327 IAZ000-190100- MESOSCALE DISCUSSION 0548 NWS STORM PREDICTION CENTER NORMAN OK 0627 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/SRN IA. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182327Z - 190100Z SEVERE POTENTIAL IS INCREASING ACROSS PORTIONS CENTRAL/SRN IA. AREA IS BEING MONITORED FOR POSSIBLE WW. SFC MESOANALYSIS SHOWS OCCLUDED FRONT NEAR LINE FROM 20 N FSD...50 W DSM...35 NE STJ. THIS FRONT SHOULD FORM CONTINUE MOVING EWD 15-20 KT ACROSS WRN IA...DENOTING WRN EDGE OF SIGNIFICANT CONVECTIVE POTENTIAL. DISCRETE AND POTENTIALLY SUPERCELLULAR TSTMS HAVE FORMED OVER NWRN MO PORTION OF FRONT...IN NRN PORTIONS WW 199...WITH ADDITIONAL DEVELOPMENT POSSIBLE FARTHER N. ALTHOUGH MODIFIED RUC SOUNDINGS INDICATE STRONG SBCINH...FAVORABLE MUCAPES AND VERTICAL SHEAR PROFILES ARE EVIDENT IN PROFILER DATA AND MODIFIED RAOBS. EXPECT AT LEAST FEW SEVERE TSTMS TO MOVE NEWD ACROSS THIS AREA ALONG/AHEAD OF FRONT. MOST PROBABLE NEAR-TERM RISK WILL BE ACROSS PORTIONS DECATUR/WAYNE/LUCAS/MONROE/APPANOOSE COUNTIES...INVOF PROJECTED TRACKS OF MO TSTMS. MAIN THREAT IS LARGE HAIL. PROSPECTIVE INFLOW LAYER WILL BECOME PROGRESSIVELY MORE ELEVATED WITH NWD EXTENT...INDICATING DIMINISHING WIND/TORNADO POTENTIAL NWD ACROSS DISCUSSION AREA. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DVN...DMX... 40609411 41239431 41709430 42199414 42499371 42439315 42159275 41309245 40609225 WWWW From Mcd at goshenarc.org Tue Apr 18 23:52:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 19:52:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 182350 SWOMCD SPC MCD 182349 WIZ000-MNZ000-190215- MESOSCALE DISCUSSION 0549 NWS STORM PREDICTION CENTER NORMAN OK 0649 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN MN...EXTREME WRN WI. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 182349Z - 190215Z BAND OF SCATTERED TSTMS SHOULD MAINTAIN RISK FOR OCNL/MRGL SEVERE HAIL AS IT MOVES NWD TO NNEWD ACROSS MN AND PERHAPS WRN TIER WI COUNTIES N RST. WW NOT ANTICIPATED ATTM. SFC ANALYSIS SHOWS OCCLUDED FRONT EXTENDING FROM S-CENTRAL SD CYCLONE SEWD ACROSS PIPESTONE COUNTY MN...INTO W-CENTRAL IA. ELEVATED BAND OF LIFT HAS CONTRIBUTED TO TSTM DEVELOPMENT PARALLEL TO AND ABOUT 100 NM NE OF SFC FRONT. MOST INTENSE ACTIVITY AS OF WAS LOCATED FROM MEEKER-WASECA COUNTIES...HOWEVER INTENSIFICATION IS POSSIBLE SEWD TOWARD RST AREA AND SOMEWHAT NWWD TOWARD DOUGLAS/TODD COUNTIES. VWP/PROFILER DATA SHOWS ROUGHLY 40 KT SELY LLJ AROUND 850 MB LEVEL OVER THIS REGION. ELEVATED WAA/MOIST ADVECTION INTO AREA N AND E OF CONVECTIVE BAND WILL SUPPORT ELEVATED MUCAPES ROUGHLY 1000 J/KG...WITH STEEP MIDLEVEL LAPSE RATES OF 8-9 DEG C/KM. ..EDWARDS.. 04/18/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...DLH...ARX...MPX...FGF... 43519290 44899433 45519515 45809529 46969503 46599366 45989279 45589248 44849210 WWWW From Mcd at goshenarc.org Wed Apr 19 00:52:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 20:52:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190050 SWOMCD SPC MCD 190050 TXZ000-190245- MESOSCALE DISCUSSION 0550 NWS STORM PREDICTION CENTER NORMAN OK 0750 PM CDT TUE APR 18 2006 AREAS AFFECTED...SCENTRAL/CENTRAL TX CONCERNING...SEVERE THUNDERSTORM WATCH 200... VALID 190050Z - 190245Z CLUSTER OF SVR STORMS OVER THE HILL COUNTRY WILL MOVE EWD AROUND 25 KTS INTO THE I-35 CORRIDOR FROM GEORGETOWN SWD THROUGH AUS OVER THE NEXT FEW HRS. INCREASING INHIBITION WILL LIKELY LIMIT ADDITIONAL SVR TSTM DEVELOPMENT TO THE WSW OF THIS ACTIVITY. THERFORE THE SVR TSTM THREAT APPEARS TO BE DECREASING OVER THE OVER THE SRN/WRN HILL COUNTRY /REAL...BANDERA...MEDINA...UVALDE... AND BEXAR COUNTIES/. THIS AREA IS EXPECTED TO BE CLEARED WITHIN THE NEXT HR. OBSERVED CONDITIONS OVER THE ERN HILL COUNTRY ENTERED INTO THE 00Z DRT SOUNDING INDICATES AROUND 100 J/KG OF MUCINH. WITH THE COMBINATION OF STORMS MOVING OVER LOWER ELEVATION AND INCREASING CINH AS BOUNDARY LAYER DECOUPLES OVER THE NEXT FEW HRS...EXPECT A GRADUALLY WANING SVR THREAT WITH CLUSTER OF STORMS OVER THE ERN/NRN HILL COUNTRY. HOWEVER BEFORE THAT OCCURS...LARGE HAIL/DMGG WINDS WILL REMAIN POSSIBLE THROUGH AT LEAST 02Z. NO ADDITIONAL WW IS EXPECTED EAST OF WW 200 FOR THE ABOVE REASONING. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT... 30779824 30419959 30049965 29529927 29779827 30459705 31019716 WWWW From Mcd at goshenarc.org Wed Apr 19 02:01:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 22:01:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190159 SWOMCD SPC MCD 190159 ILZ000-MOZ000-IAZ000-190330- MESOSCALE DISCUSSION 0551 NWS STORM PREDICTION CENTER NORMAN OK 0859 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS NRN/ERN MO....WRN IL. CONCERNING...TORNADO WATCH 199... VALID 190159Z - 190330Z ONE OR TWO WWS MAY BE REQUIRED E OF PRESENT WW AREA...COVERING PORTIONS MO/IL NEAR MS RIVER. BROKEN BAND OF STRONG AND SEVERE TSTMS WILL CONTINUE TO SHIFT EWD ACROSS CENTRAL/NERN MO...THEN ACROSS MS RIVER OVER PORTIONS WRN IL. SFC MESOANALYSIS SHOWS OCCLUDED FRONT FROM JUST SW DSM SSEWD TO NEAR COU...WHERE INTENSE CLUSTER OF TSTMS APPEARS TO COINCIDE WITH MESOLOW/TRIPLE POINT. WARM FRONT EXTENDS SEWD FROM THAT AREA TO NEAR SRN TIP OF IL...AND SHOULD LIFT NEWD ABOUT 10 KT. OCCLUDED/COLD FRONT WILL CONTINUE MOVING EWD 20-25 KT ACROSS CENTRAL MO. THIS WILL PRODUCE ESEWD-PROPAGATING ZIPPER EFFECT FOR TRIPLE POINT TOWARD AREA NEAR OR JUST SW STL. VERTICAL SHEAR PROFILES WILL REMAIN FAVORABLE FOR BOTH SUPERCELLS AND BOW ECHOES. RUC SOUNDINGS OVER ERN MO NEAR WARM FRONT...AND VWP FROM STL AREA...ON COOL SIDE OF WARM FRONT -- ARE QUITE FAVORABLE WITH 0-3 KM SRH 300-500 J/KG. TORNADO/DAMAGING WIND POTENTIAL SHOULD BE MAXIMIZED AROUND OCCLUSION TRIPLE POINT REGION AND SLGTLY SEWD ALONG WARM FRONT. BOUNDARY LAYER AIR MASS SW OF WARM FRONT WILL STABILIZE GRADUALLY THROUGH REMAINDER EVENING...HOWEVER MODIFIED RUC SOUNDINGS SUGGEST EFFECTIVE PARCELS IN WARM SECTOR WILL REMAIN ROOTED NEAR SFC FOR SEVERAL MORE HOURS. MAIN THREAT N OF TRIPLE POINT WILL BE HAIL...WHERE BUOYANCY IS ROOTED AGL. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...ILX...LSX...DVN...SGF...EAX... 37549252 38659239 39739284 40359357 40509339 40549195 40589077 40269045 39909016 39248983 38648962 38058959 37648966 37429018 WWWW From Mcd at goshenarc.org Wed Apr 19 02:46:06 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 22:46:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190243 SWOMCD SPC MCD 190243 ARZ000-LAZ000-TXZ000-OKZ000-190445- MESOSCALE DISCUSSION 0552 NWS STORM PREDICTION CENTER NORMAN OK 0943 PM CDT TUE APR 18 2006 AREAS AFFECTED...MUCH OF CENTRAL AR / FAR SERN OK AND NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 190243Z - 190445Z A GRADUAL INCREASE IN DEEP CONVECTION IS ANTICIPATED ALONG THE COLD FRONT THROUGH THE EVENING. LARGE HAIL WOULD BE THE MAIN SEVERE THREAT. RADAR ECHOES CONTINUE TO INCREASE ACROSS WRN AR ALONG COLD FRONT. 00Z LZK SOUNDING SHOWS VERY STEEP MID LEVEL LAPSE RATES IN PLACE. STRONG INSTABILITY EXISTS WHEN MODIFIED FOR MID 60S BOUNDARY LAYER DEWPOINTS AS SEEN ON UPSTREAM SHV SOUNDING. SOME CAPPING EXISTS...BUT DEEP MOISTURE CONVERGENCE ALONG COLD FRONT SHOULD BE ENOUGH TO GET AT LEAST ISOLATED SVR CONVECTION GOING. AREA VWPS INDICATE STRONG LOW LEVEL WARM ADVECTION PROFILE WHICH WILL MAINTAIN FEED OF HIGHER THETA-E AIR INTO THE FRONTAL ZONE. ..JEWELL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SHV...TSA...FWD... 35509348 35999287 36329196 36489136 36299067 35719070 34609180 33389297 32949402 32739476 32789542 33169600 33599595 34109517 WWWW From Mcd at goshenarc.org Wed Apr 19 03:39:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 18 Apr 2006 23:39:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190337 SWOMCD SPC MCD 190336 ILZ000-IAZ000-MOZ000-190530- MESOSCALE DISCUSSION 0553 NWS STORM PREDICTION CENTER NORMAN OK 1036 PM CDT TUE APR 18 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN IA...W-CENTRAL/NWRN IL...NERN MO. CONCERNING...SEVERE THUNDERSTORM WATCH 201...202... VALID 190336Z - 190530Z SEVERE TSTM POTENTIAL --- PRIMARILY LARGE HAIL WITH ISOLATED DAMAGING WIND -- SHOULD CONTINUE TO SHIFT EWD ACROSS WWS AND MAY EXTEND EWD INTO EXTREME ERN IA AND NWRN IL. SEVERAL REPORTS OF MAINLY 1 INCH AND SMALLER DIAMETER HAIL HAVE BEEN RECEIVED OVER WWS DURING PAST 1-2 HOURS. SINCE HAIL THREAT SHOULD REMAIN MRGLLY SEVERE...AND LIKELY NOT AS NUMEROUS AS FARTHER W ACROSS NRN MO AND IA...WW NOT PLANNED ATTM. HOWEVER...WILL CONTINUE TO MONITOR. TWO PRIMARY BANDS OF CONVECTION ARE EVIDENT AS OF 315Z...FIRST FROM NWRN PORTIONS WW 213 NWD TO NEAR UIN/BRL. THIS ACTIVITY WILL MOVE E OF WWS SHORTLY...WITH POTENTIAL FOR ISOLATED HAIL NEAR SEVERE LEVELS. TSTMS IN OTHER BAND -- GENERALLY BETWEEN MCW AND 20 SW IRK -- WILL MOVE NEWD ACROSS REMAINDER WRN/NRN PORTIONS WW 201...AND FROM NERN PORTIONS WW 199 INTO SERN IA AND EXTREME NERN MO. MODIFIED RUC FCST SOUNDINGS SHOW FAVORABLE THERMODYNAMIC PROFILES OVER SRN IA/IL BORDER REGION...AMIDST STRONG LOW LEVEL WAA PROFILES. EXPECT 8-9 DEG C/KM MIDLEVEL LAPSE RATES...AND MUCAPES AROUND 1500 J/KG...WITH BUOYANCY ROOTED IN 750-850 MB LAYER. HOWEVER...RELATIVELY WEAK MIDLEVEL WINDS CONTRIBUTE TO ONLY 20-30 KT EFFECTIVE SHEARS...WITH LIMITED POTENTIAL FOR WELL-ORGANIZED LARGE HAIL EVENT. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILX...LSX...DVN...DMX...EAX... 38889144 39359154 40479216 40509309 41439330 42009390 42739379 42739248 42189080 41508970 40378960 39098984 WWWW From Mcd at goshenarc.org Wed Apr 19 05:03:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 01:03:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190501 SWOMCD SPC MCD 190500 ILZ000-MOZ000-190600- MESOSCALE DISCUSSION 0554 NWS STORM PREDICTION CENTER NORMAN OK 1200 AM CDT WED APR 19 2006 AREAS AFFECTED...PORTIONS ERN MO...CENTRAL/SRN IL. CONCERNING...TORNADO WATCH 203... VALID 190500Z - 190600Z PRIMARY SEVERE POTENTIAL WILL REMAIN ASSOCIATED WITH LONG-LIVED/COMPLEX CLUSTER OF SEVERE TSTMS MOVING ESEWD FROM JEFFERSON COUNTY MO. PORTIONS STE. GENEVIEVE/PERRY COUNTIES MO...AND MONROE/RANDOLPH/JACKSON/PERRY COUNTIES IL ARE IN PATH OF THIS ACTIVITY...WHICH CONTINUES TO POSE RISK OF DAMAGING GUSTS...HAIL AND POSSIBLY A TORNADO OR TWO. CONVECTION SHOULD REMAIN LOCATED INVOF OCCLUSION TRIPLE POINT WHERE MOIST BUOYANT PARCELS ARE LOCATED...AS WELL AS MAXIMIZED LOW LEVEL HODOGRAPHS. FARTHER E AND NE ACROSS PORTIONS CENTRAL/SRN IL...ELEVATED MUCAPES AROUND 1000 J/KG ARE EVIDENT...BASED ON MODIFIED RAOBS AND RUC SOUNDINGS. THIS WILL CONTINUE TO SUPPORT SCATTERED TSTMS WITH OCCASIONAL HAIL...THROUGH VERTICAL SHEAR PROFILES IN LOW-MIDLEVELS OF BUOYANT LAYER SHOULD REMAIN RELATIVELY WEAK. MEANWHILE...GUST FRONT HAS MOVED WELL AHEAD OF MOST REFLECTIVITY CORES ASSOCIATED WITH W-CENTRAL IL LINE...BUT STILL PRODUCED MEASURED 51 KT GUST AT IJX OB AT 425Z. EXPECT DAMAGING WIND POTENTIAL WITH THIS GUST FROM TO DIMINISH WITH EWD EXTENT INTO PROGRESSIVELY MORE STABLE BOUNDARY LAYER...AND AS PARENT CONVECTION REMAINS REMOVED BY SEVERAL MILES OR MORE FROM LEADING EDGE OF OUTFLOW. ..EDWARDS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...ILX...LSX... 37079080 37399062 38259075 39059001 39458886 39388780 38928761 37888834 37158929 WWWW From Mcd at goshenarc.org Wed Apr 19 06:42:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 02:42:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190640 SWOMCD SPC MCD 190640 SDZ000-NDZ000-MTZ000-WYZ000-191245- MESOSCALE DISCUSSION 0555 NWS STORM PREDICTION CENTER NORMAN OK 0140 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN MT AND THE BLACK HILLS REGION CONCERNING...HEAVY SNOW AND NEAR BLIZZARD CONDITIONS VALID 190640Z - 191245Z HEAVY SNOW IS EXPECTED THROUGH THE NIGHT WITH HRLY RATES OF AT LEAST 1 IN/HR. STRONG WINDS WILL FURTHER MAINTAIN NEAR BLIZZARD CONDITIONS. RADAR TRENDS INDICATE AN INCREASING BAND OF SNOW ACROSS WRN SD AS OF 630Z...WHICH IS IN AGREEMENT WITH LATEST RUC/NAM/WRF MODELS INDICATING INCREASING PRECIPITATION RATES THROUGH 12Z ACROSS FAR SERN MT AND WRN SD. STRONG NWLY UPSLOPE FLOW WILL KEEP HEAVIEST PRECIP. RATES FOCUSED ACROSS THE NRN BLACK HILLS. WHILE WINDS WILL BE STRONG...RELATIVELY WARM TEMPERATURES IN THE 30S WILL HELP MITIGATE DRIFTING...ALTHOUGH VISIBILITIES WILL BE REDUCED TO ZERO AT TIMES. ..JEWELL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...UNR...BYZ...GGW... 44690489 45570542 46350565 46820527 46910440 46440356 46180344 45180310 44400308 43940346 43930422 WWWW From Mcd at goshenarc.org Wed Apr 19 07:05:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 03:05:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190703 SWOMCD SPC MCD 190702 TNZ000-VAZ000-NCZ000-KYZ000-190900- MESOSCALE DISCUSSION 0556 NWS STORM PREDICTION CENTER NORMAN OK 0202 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN KY THROUGH NERN TN AND EXTREME SWRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 190702Z - 190900Z THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE AND INTENSITY THIS MORNING. LARGE HAIL WILL BE THE PRIMARY THREAT. AREA IS BEING MONITORED FOR A POSSIBLE WW. A PLUME OF STEEP MID LEVEL LAPSE RATES HAS SPREAD EWD INTO PARTS OF THE TN VALLEY. MEANWHILE...A SWLY LOW LEVEL JET CONTINUES TO ADVECT HIGHER THETA-E AIR NEWD BENEATH THE PLUME OF STEEP LAPSE RATES CONTRIBUTING TO MODERATE ELEVATED INSTABILITY WITH MUCAPE AROUND 1500 J/KG. THE LOW LEVEL JET IS FORECAST TO VEER AND SHIFT EWD THROUGH THE TN VALLEY NEXT FEW HOURS WITH WARM ADVECTION AND ISENTROPIC ASCENT BECOMING MAXIMIZED ACROSS PORTIONS OF NERN TN AND SERN KY ON THE COOL SIDE OF A NW-SE ORIENTED STATIONARY FRONT. LATEST RADAR DATA ALREADY SHOW ELEVATED STORMS INCREASING IN THIS AREA...AND THIS TREND IS EXPECTED TO PERSIST THROUGH THE EARLY MORNING HOURS. IN ADDITION TO STEEP MID LEVEL LAPSE RATES AND MODERATE INSTABILITY...CLOUD LAYER SHEAR IS SUFFICIENT FOR UPDRAFTS TO ROTATE WHICH WILL ENHANCE THE POTENTIAL FOR HAIL WITH THE STRONGER STORMS. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...JKL...LMK... 36408250 35718305 35518412 36348439 37158496 37418391 WWWW From Mcd at goshenarc.org Wed Apr 19 08:46:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 04:46:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 190844 SWOMCD SPC MCD 190843 KYZ000-191015- MESOSCALE DISCUSSION 0557 NWS STORM PREDICTION CENTER NORMAN OK 0343 AM CDT WED APR 19 2006 AREAS AFFECTED...SWRN KY...S CNTRL KY THROUGH EXTREME SRN IND CONCERNING...TORNADO WATCH 205... VALID 190843Z - 191015Z LINE OF STRONG TO SEVERE STORMS IS EXPECTED TO CONTINUE EWD NEXT FEW HOURS. BEST THREAT FOR AN ISOLATED TORNADO OR TWO EXISTS ON SRN END OF THE LINE ACROSS SWRN KY. OTHERWISE LARGE HAIL AND ISOLATED DAMAGING WIND ARE LIKELY WITH THE STRONGER STORMS. CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED FOR A POSSIBLE WW DOWNSTREAM ACROSS S CNTRL KY. EARLY THIS MORNING A LINE OF SEVERE STORMS PERSISTS FROM EXTREME SRN IND SWD INTO SWRN KY. THE 0-3 KM HODOGRAPHS REMAIN LARGE AND FAVORABLE FOR ORGANIZED STORM STRUCTURES INCLUDING SUPERCELLS. HOWEVER...THE LINE IS MOSTLY OUTFLOW DOMINANT WITH THE EXCEPTION OF STORMS ON THE SRN END OF THE LINE. THIS SUGGESTS BEST CHANCE FOR AN ISOLATED TORNADO OR TWO WILL PERSIST WITH SRN END STORMS PRIOR TO BEING UNDERCUT BY THE SURGING OUTFLOW BOUNDARY. ACTIVITY IS MOVING ESEWD AT 35 TO 40 KT AND WILL APPROACH THE ERN EDGE OF WW 205 BY 0915-0930Z. MODERATE INSTABILITY PERSISTS DOWNSTREAM FROM THE LINE AND NEW STORMS MAY CONTINUE TO DEVELOP WITHIN ZONE OF ASCENT AND CONVERGENCE ALONG THE OUTFLOW BOUNDARY NEXT COUPLE HOURS. IF STORMS SHOW SIGNS OF MAINTAINING THEIR INTENSITY...ANOTHER WW MIGHT BE NEEDED E OF WW 205. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...PAH... 36998787 37188757 37478735 37838694 37348623 36658624 36708773 WWWW From Mcd at goshenarc.org Wed Apr 19 11:30:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 07:30:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191128 SWOMCD SPC MCD 191128 NCZ000-VAZ000-TNZ000-KYZ000-191230- MESOSCALE DISCUSSION 0558 NWS STORM PREDICTION CENTER NORMAN OK 0628 AM CDT WED APR 19 2006 AREAS AFFECTED...PORTIONS OF MIDDLE AND NERN TN...SERN KY...SWRN VA AND WRN NC CONCERNING...SEVERE THUNDERSTORM WATCH 206...207... VALID 191128Z - 191230Z OVERALL TREND HAS BEEN FOR STORMS IN WW 206 TO WEAKEN...BUT ISOLATED HAIL REMAINS POSSIBLE WITH THE STRONGER CELLS. A LINE OF STRONG STORMS CONTINUES IN WW 207 FROM S CNTRL KY INTO NRN PORTIONS OF MIDDLE TN. THE THREAT FOR ISOLATED HAIL AND POSSIBLY STRONG WIND GUSTS IS EXPECTED TO PERSIST ANOTHER COUPLE HOURS. SOME OF THIS ACTIVITY WILL SHIFT EWD INTO WRN PORTIONS OF WW 206 THIS MORNING. PORTIONS OF SERN TN WILL BE MONITORED FOR A POSSIBLE WW LATER THIS MORNING. THE LOW LEVEL JET HAS VEERED TO WLY ACROSS TN. WARM ADVECTION AND ISENTROPIC ASCENT CONTINUES TO SUPPORT THUNDERSTORM DEVELOPMENT FROM SERN KY...SWRN VA...NERN TN AND WRN NC. HOWEVER...OVERALL TREND HAS BEEN FOR STORMS TO WEAKEN AS INITIAL STRONG CELLS HAVE MERGED...RESULTING IN A FAIRLY WIDESPREAD STRATIFORM REGION OVER PARTS OF NERN TN INTO WRN NC. SOME OF THE STRONGER CELLS ON THE PERIPHERY OF THE STRATIFORM RAIN AREA MAY STILL BE CAPABLE OF PRODUCING MARGINALLY SEVERE HAIL. OTHER STORMS ARE DEVELOPING FARTHER W FROM S CNTRL KY SWD INTO NRN PARTS OF MIDDLE TN. STORMS ARE EXPECTED TO CONTINUE DEVELOPING ALONG THE GUST FRONT AND ARE BEGINNING TO SPREAD INTO NWRN PORTIONS OF WW 206. STRONGEST STORMS ARE EXPECTED TO PERSIST ON THE SRN END OF THE LINE. THE DECOUPLED BOUNDARY LAYER HAS SO FAR SERVED AS A LIMITING FACTOR FOR WIDESPREAD DAMAGING WIND. HOWEVER...AS HEATING COMMENCES...SOME RE-INTENSIFICATION MAY OCCUR...ESPECIALLY ACROSS PARTS OF SERN TN...AND THIS AREA WILL BE MONITORED FOR A POSSIBLE WW LATER THIS MORNING. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...GSP...MRX...JKL...LMK...OHX... 35278335 35928542 36118612 36748538 37378479 37528315 37028239 35498151 WWWW From Mcd at goshenarc.org Wed Apr 19 13:00:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 09:00:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191258 SWOMCD SPC MCD 191258 GAZ000-NCZ000-TNZ000-191500- MESOSCALE DISCUSSION 0559 NWS STORM PREDICTION CENTER NORMAN OK 0758 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN TN THROUGH NWRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191258Z - 191500Z THUNDERSTORMS MAY INTENSIFY LATER THIS MORNING AS THEY DEVELOP SEWD THROUGH SERN TN AND INTO NWRN GA. DAMAGING WIND AND LARGE HAIL WILL BE THE PRIMARY THREATS. AREA WILL BE MONITORED FOR A POSSIBLE WW WITHIN THE NEXT COUPLE HOURS. EARLY THIS MORNING A SQUALL LINE WAS MOVING SEWD THROUGH ERN TN AT AROUND 35 KT. THE 12Z RAOB FROM ATL SHOWS THE BOUNDARY LAYER TO BE STABLE...BUT WITH MODERATE MUCAPE AND STEEP LAPSE RATES ABOVE THE BOUNDARY LAYER. WIDESPREAD CLOUDS EXIST THIS MORNING ACROSS MUCH OF GA...BUT THESE CLOUDS ARE EXPECTED TO BEGIN TO MIX OUT FROM THE NW ALLOWING THE BOUNDARY LAYER TO DESTABILIZE. STEEP LAPSE RATES UPSTREAM WILL SPREAD EWD ABOVE THE MOIST BOUNDARY LAYER AND CONTRIBUTE TO FURTHER DESTABILIZATION AS SURFACE HEATING COMMENCES. RAOB DATA SUGGEST SURFACE TEMPERATURES IN THE MID 70S ARE NEEDED FOR STORMS TO BECOME SURFACE BASED...AND THIS WILL LIKELY OCCUR AS THE BOUNDARY LAYER CONTINUES TO WARM DOWNSTREAM FROM THE SEWD ADVANCING STORMS. THE LOW LEVEL FLOW IS FORECAST TO GRADUALLY WEAKEN...BUT DEEP LAYER SHEAR PROFILES WILL REMAIN SUFFICIENT FOR ORGANIZED STORM STRUCTURES INCLUDING BOW ECHOES AND SUPERCELLS. ..DIAL.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC... 33848478 35068565 35288447 34728415 34028400 WWWW From Mcd at goshenarc.org Wed Apr 19 16:59:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 12:59:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191657 SWOMCD SPC MCD 191656 SCZ000-GAZ000-191900- MESOSCALE DISCUSSION 0560 NWS STORM PREDICTION CENTER NORMAN OK 1156 AM CDT WED APR 19 2006 AREAS AFFECTED...SERN GA/SRN SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191656Z - 191900Z SEVERE THREAT EXPECTED TO SLOWLY INCREASE ACROSS SERN GA OVER THE NEXT FEW HOURS. NEW WW IS ANTICIPATED...THOUGH NOT IMMINENT. LESSER SEVERE THREAT -- MAINLY IN THE FORM OF HAIL -- ALSO EXPECTED WITH MAINLY ELEVATED STORMS ACROSS SRN SC THROUGH THE AFTERNOON. BOUNDARY LAYER IS DESTABILIZING ACROSS SERN GA...AS DAYTIME HEATING CONTINUES PER LATEST SURFACE OBS/VISIBLE SATELLITE IMAGERY SOUTHWEST OF NW-SE OUTFLOW BOUNDARY GENERATED BY ONGOING CONVECTION OVER NRN AND ERN GA/SC. THIS BOUNDARY CURRENTLY EXTENDS FROM NWRN GA SEWD ACROSS CENTRAL GA TO NEAR SAV...SW OF WHICH INSTABILITY HAS INCREASED TO AROUND 500 J/KG MEAN-LAYER CAPE. THOUGH VARIOUS MODEL SOUNDINGS REVEAL CAPPED BOUNDARY LAYER EARLY THIS AFTERNOON -- CONFIRMED BY GRAVITY WAVE APPARENT IN VISIBLE LOOP...CONTINUED HEATING/MIXING COMBINED WITH LIFT INVOF OUTFLOW BOUNDARY SHOULD PROVE SUFFICIENT FOR CONVECTIVE DEVELOPMENT. WITH LOW-LEVEL FLOW VEERING/INCREASING TO NWLY AT 40 TO 45 KT AT MID LEVELS...THREAT FOR ORGANIZED SEVERE STORMS EXISTS. THOUGH SUPERCELLS WILL BE POSSIBLE...IT APPEARS MOST LIKELY THAT STORMS SHOULD ORGANIZED INTO A SEWD-MOVING LINE/BOW WITH TIME...CAPABLE OF DAMAGING WINDS AND HAIL. FURTHER NW -- ON COOL SIDE OF OUTFLOW BOUNDARY ACROSS SC...STRONG/LOCALLY SEVERE STORMS SHOULD CONTINUE MOVING SEWD ACROSS THIS REGION. THOUGH LOCAL HEATING MAY ALLOW SUFFICIENT SURFACE-BASED DESTABILIZATION FOR LIMITED DAMAGING WIND POTENTIAL...HAIL SHOULD REMAIN THE MORE LIKELY SEVERE THREAT. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...CAE...JAX...FFC...TAE... 33488348 33698236 33748153 32738008 30978152 30688369 32098418 33048418 WWWW From Mcd at goshenarc.org Wed Apr 19 17:37:36 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 13:37:36 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191735 SWOMCD SPC MCD 191735 MSZ000-LAZ000-ARZ000-TXZ000-191930- MESOSCALE DISCUSSION 0561 NWS STORM PREDICTION CENTER NORMAN OK 1235 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN TX...FAR SRN AR AND NRN LA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 191735Z - 191930Z ISOLATED SVR STORMS /WITH LARGE HAIL THE PRIMARY THREAT/ MAY DEVELOP BY 19Z OVER THE ARKLATEX AREA EWD ALONG THE AR/LA BORDER. AREA CONTINUES TO BE MONITORED FOR A POSSIBLE WW. 17Z SURFACE MESOANALYSIS PLACES A MESOLOW OVER FAR NERN TX NEAR GGG...WITH A STATIONARY FRONT EXTENDING EWD FROM THE LOW ALONG THE AR/LA BORDER. MODIFIED 12Z SHV SOUNDING FOR 17Z SFC CONDITIONS INDICATES LESS THAN 50 J/KG OF MLCINH REMAINS WITH MODERATE CU OBSERVED RECENTLY ON VIS SAT IMAGERY JUST EAST OF GGG. ENHANCED CONVERGENCE IN THE VICINITY OF THE MESOLOW AND CONTINUED BOUNDARY LAYER HEATING/DIMINISHING CINH MAY BE ENOUGH SUPPORT FOR ISOLATED CONVECTIVE DEVELOPMENT IN THE NEXT 2 HRS. DESPITE MARGINAL EFFECTIVE LAYER SHEAR FOR ORGANIZED STORM ROTATION /35-40 KTS PER RECENT DE QUEEN AND PALESTINE PROFILER DATA /...MODERATE TO STRONG INSTABILITY /MLCAPES AROUND 2500 J/KG / WILL AID IN STRONG UPDRAFT INTENSITY AND POTENTIAL FOR LARGE HAIL. IN ADDITION...MID LEVEL THERMAL TROUGH /EVIDENT PER ACCAS FIELD ON SAT DATA/ SUGGESTS STEEP MID LEVEL LAPSE RATES /AROUND 8 DEG C/KM / FURTHER SUPPORTING THREAT FOR LARGE SVR HAIL. ALONG WITH THE POTENTIAL FOR SURFACE INITIATED SVR CONVECTION ALONG THE STATIONARY BOUNDARY...SOME OF THIS ACCAS MAY EVENTUALLY BECOME ROOTED IN THE BOUNDARY LAYER /AND BECOME SVR/ AS IT MOVES ENEWD ACROSS NRN LA THIS AFTERNOON. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV... 33419209 33299303 33209380 33139417 32779466 32449490 31959488 31659435 31609364 31779186 32349099 33199132 WWWW From Mcd at goshenarc.org Wed Apr 19 18:42:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 14:42:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191840 SWOMCD SPC MCD 191839 GAZ000-ALZ000-192015- MESOSCALE DISCUSSION 0562 NWS STORM PREDICTION CENTER NORMAN OK 0139 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN AL/NWRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 208... VALID 191839Z - 192015Z STRONG/SEVERE STORMS CONTINUE -- MOST OF WHICH REMAIN SLIGHTLY ELEVATED ON THE COOL SIDE OF SWWD-MOVING OUTFLOW BOUNDARY WHERE WARM ADVECTION ASSOCIATED WITH WLY LOW-LEVEL JET IS MAXIMIZED. STEEP LAPSE RATES JUST OFF THE SURFACE CONTINUE TO SUPPORT MODERATE TO STRONG INSTABILITY...REFLECTED BY OBJECTIVELY-ANALYZED 3500 TO 4000 J/KG MEAN-LAYER CAPE ACROSS NERN MS/NWRN AL -- W OF OUTFLOW WITHIN WARM SECTOR. THOUGH SOME POTENTIAL REMAINS FOR STORMS TO DEVELOP NEAR -- AND THEN ORGANIZE AND RIDE SEWD ALONG -- SURFACE OUTFLOW BOUNDARY...IN WHICH CASE THREAT FOR DAMAGING WINDS WOULD INCREASE...IT APPEARS THAT MAIN SEVERE THREAT MAY REMAIN HAIL WITH SLIGHTLY-ELEVATED STORMS ON COOL SIDE OF OUTFLOW. WITH OUTFLOW BOUNDARY -- AND ASSOCIATED STORM DEVELOPMENT -- CONTINUING TO PROGRESS SWWD TOWARD WRN PORTIONS OF WW OVER AL...THREAT MAY SPILL JUST W OF CURRENT WW AREA WITH TIME. HOWEVER...OVERALL WWD EXTENT OF THREAT SHOULD BE LIMITED BY APPARENT PRE-FRONTAL TROUGH/CONVERGENCE AXIS MOVING SLOWLY EWD ACROSS NWRN AL. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN... 34958591 34268384 33008303 32378555 32918768 34938746 WWWW From Mcd at goshenarc.org Wed Apr 19 19:33:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 15:33:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 191931 SWOMCD SPC MCD 191931 GAZ000-ALZ000-192100- MESOSCALE DISCUSSION 0564 NWS STORM PREDICTION CENTER NORMAN OK 0231 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN AND ERN AL/W CENTRAL GA CONCERNING...SEVERE THUNDERSTORM WATCH 208... VALID 191931Z - 192100Z THUNDERSTORMS CONTINUE TO DEVELOP WWD ACROSS GA INTO AL. NEW WW WILL LIKELY BE REQUIRED...TO REPLACE WW 208 WHICH IS SCHEDULED TO EXPIRE AT 20/21Z. LATEST RADAR IMAGERY CONTINUES TO SHOW SLIGHTLY-ELEVATED THUNDERSTORMS -- NOW SHOWING SUPERCELL CHARACTERISTICS -- DEVELOPING WWD ACROSS NWRN AL JUST TO THE COOL SIDE OF WSWWD-MOVING OUTFLOW BOUNDARY. ADDITIONALLY... A NEW STORM HAS DEVELOPED OVER SRN MORGAN COUNTY AL...NEAR THE INTERSECTION OF THE NW-SE OUTFLOW BOUNDARY AND NW-SW PRE-FRONTAL TROUGH. WITH WEAK SHORT-WAVE RIDGING ACROSS THIS AREA...IT APPEARS THAT STORM DEVELOPMENT WILL REMAIN LIMITED TO ZONES OF LOW-LEVEL FORCING INVOF SURFACE BOUNDARIES. THUS...EXPECT SUBSEQUENT DEVELOPMENT OF STORMS TO REMAIN TIED TO THE OUTFLOW...AND INVOF THE OUTFLOW/SURFACE TROUGH INTERSECTION. GIVEN STRONG INSTABILITY AND FAVORABLE SHEAR...CONTINUED THREAT FOR SEVERE/SUPERCELL STORMS SHOULD PERSIST INTO THE EVENING...WELL BEYOND THE 21Z EXPIRATION OF WW 208. THEREFORE...NEW WW WILL LIKELY BE ISSUED SHORTLY...ADDRESSING THE ONGOING THREAT FOR HAIL AND THE POTENTIAL FOR LOCALLY DAMAGING WINDS AND/OR A COUPLE TORNADOES. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...HUN... 34708535 33258393 32248338 31698536 32888728 34938746 WWWW From Mcd at goshenarc.org Wed Apr 19 20:21:30 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:21:30 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192019 SWOMCD SPC MCD 192018 TXZ000-192215- MESOSCALE DISCUSSION 0565 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT WED APR 19 2006 AREAS AFFECTED...CENTRAL/NCENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192018Z - 192215Z ISOLATED SVR HAIL MAY BE POSSIBLE WITH DEVELOPING ELEVATED CONVECTION AS IT MOVES FROM SWRN INTO CENTRAL/NCENTRAL TX THROUGH THE REST OF THE AFTERNOON. ATTM A WW IS NOT ANTICIPATED BUT TRENDS WILL CONTINUE TO BE MONITORED. REGIONAL VWP DATA INDICATES THAT THE STRONGEST WARM ADVECTION WAS LOCATED IN THE 1-2 KM LAYER. IN THIS LAYER...MOISTURE WAS INCREASING BENEATH A CAPPING INVERSION CENTERED AROUND 3 KM. SUFFICIENT MOISTENING/ASCENT HAS DEVELOPED OVER THE LAST 1-2 HRS TO INITIATE A FEW ELEVATED SHOWERS/TSTMS OVER SWRN TX 50-75 MILES NORTH OF THE SFC FRONTAL BOUNDARY. INSPECTION OF RECENT RUC/NAM FORECAST SOUNDINGS INDICATE AROUND 1500-2000 J/KG OF ELEVATED MUCAPE IS POSSIBLE IF THE MID LEVEL CAPPING INVERSION IS NEGATED. GIVEN THE RELATIVELY WEAK ISENTROPIC ASCENT EXPECTED THROUGH 00Z...IT IS UNCERTAIN IF THE COVERAGE AND/OR INTENSITY OF THIS CONVECTION THAT RECENTLY DEVELOPED WILL INCREASE. HOWEVER...IF CONVECTION BEGINS TO INCREASE IN INTENSITY...FAVORABLE THERMODYNAMIC PARAMETERS COMBINED WITH 40-50 KTS OF EFFECTIVE SHEAR BE SUPPORTIVE OF A THREAT FOR SVR HAIL NEWD INTO NCENTRAL TX. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...SJT... 33219708 31750007 30930076 30670058 30789931 31689762 32339650 33139607 33309639 WWWW From Mcd at goshenarc.org Wed Apr 19 20:43:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:43:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192040 SWOMCD SPC MCD 192040 GAZ000-FLZ000-ALZ000-192245- MESOSCALE DISCUSSION 0566 NWS STORM PREDICTION CENTER NORMAN OK 0340 PM CDT WED APR 19 2006 AREAS AFFECTED...SRN GA/SERN AL/NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192040Z - 192245Z SEVERE THREAT INCREASING ALONG OUTFLOW BOUNDARY ACROSS SERN AL/SRN GA. NEW WW MAY BE REQUIRED. MOIST/UNSTABLE AIRMASS /MEAN-LAYER CAPE 1000 TO 1500 J/KG/ IS INDICATED NEAR AND S OF MAIN OUTFLOW BOUNDARY...WHICH CURRENTLY EXTENDS FROM LEE COUNTY AL ESEWD ACROSS SRN GA TO COASTAL AREAS OF CHATHAM/LIBERTY/BRYAN COUNTIES IN SERN GA. CONVECTIVE TOWERS ARE EVIDENT ALONG THIS BOUNDARY...ALONG WITH A FEW THUNDERSTORMS OVER COASTAL SE GA...NEAR INTERSECTION OF THE BOUNDARY WITH A WWD-MOVING SEA-BREEZE BOUNDARY. THOUGH INSTABILITY AND SHEAR ARE SOMEWHAT MORE LIMITED ACROSS THIS REGION AS OPPOSED TO AREAS FURTHER N...PARAMETERS ARE NONETHELESS SUPPORTIVE OF SEVERE THREAT. THOUGH CAPPING HAS HELD CONVECTION IN CHECK THUS FAR...EXPECT AN INCREASE IN STORMS OVER THE NEXT COUPLE OF HOURS THROUGH PEAK DIURNAL HEATING PERIOD. WITH THREAT FOR HAIL AND DAMAGING WINDS LIKELY TO ACCOMPANY ANY VIGOROUS UPDRAFTS WHICH DEVELOP...NEW WW MAY BE REQUIRED. ..GOSS.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...JAX...FFC...TAE...BMX... 31818127 31178146 30398153 30248246 30558451 31318549 32208608 32258545 31778348 WWWW From Mcd at goshenarc.org Wed Apr 19 20:52:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:52:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192050 SWOMCD SPC MCD 192050 MSZ000-ARZ000-LAZ000-TXZ000-192245- MESOSCALE DISCUSSION 0567 NWS STORM PREDICTION CENTER NORMAN OK 0350 PM CDT WED APR 19 2006 AREAS AFFECTED...FAR SRN AR...ECENTRAL/NERN TX AND NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 192050Z - 192245Z CONTINUE ALL OF WW 209. ELEVATED CONVECTION HAS YET TO BECOME ROOTED IN THE BOUNDARY LAYER AND STRENGTHEN. SINCE IT/S STILL RELATIVELY EARLY IN THE AFTERNOON...THERE REMAINS SOME POTENTIAL FOR THIS CONVECTION TO STILL BECOME ROOTED AND INTENSIFY AS CINH REMAINS RELATIVELY LOW OVER NRN LA/ECENTRAL TX. ALSO...RECENT SAT IMAGERY SHOWS THAT CINH REMAINS WEAK OVER NRN PORTIONS OF WW 209 AS TOWERING CU IS EVIDENT OVER FAR NERN TX /IN THE VICINITY OF A MESOLOW/ AND TO A LESSER EXTENT ALONG THE STATIONARY BOUNDARY ACROSS FAR SRN AR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33409302 33619414 33379475 32669539 31419540 31039532 31969102 33769120 WWWW From Mcd at goshenarc.org Wed Apr 19 20:58:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 16:58:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192055 SWOMCD SPC MCD 192055 MSZ000-ARZ000-LAZ000-TXZ000-192300- MESOSCALE DISCUSSION 0567 NWS STORM PREDICTION CENTER NORMAN OK 0355 PM CDT WED APR 19 2006 AREAS AFFECTED...FAR SRN AR...ECENTRAL/NERN TX AND NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 192055Z - 192300Z CONTINUE ALL OF WW 209. ELEVATED CONVECTION HAS YET TO BECOME ROOTED IN THE BOUNDARY LAYER AND STRENGTHEN. SINCE IT/S STILL RELATIVELY EARLY IN THE AFTERNOON...THERE REMAINS SOME POTENTIAL FOR THIS CONVECTION TO STILL BECOME ROOTED AND INTENSIFY AS CINH REMAINS RELATIVELY LOW OVER NRN LA/ECENTRAL TX. ALSO...RECENT SAT IMAGERY SHOWS THAT CINH REMAINS WEAK OVER NRN PORTIONS OF WW 209 AS TOWERING CU IS EVIDENT OVER FAR NERN TX /IN THE VICINITY OF A MESOLOW/ AND TO A LESSER EXTENT ALONG THE STATIONARY BOUNDARY ACROSS FAR SRN AR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33409302 33619414 33379475 32669539 31419540 31039532 31969102 33769120 WWWW From Mcd at goshenarc.org Wed Apr 19 21:52:38 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 17:52:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192150 SWOMCD SPC MCD 192150 ALZ000-MSZ000-192315- MESOSCALE DISCUSSION 0568 NWS STORM PREDICTION CENTER NORMAN OK 0450 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN CNTRL MS...WRN AL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192150Z - 192315Z SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER THE NEXT 1-2 HOURS ACROSS NRN MS WITH CONVECTION EXPANDING IN COVERAGE AND DRIFTING SSEWD ACROSS ERN MS AND WRN AL. A WW WILL LIKELY BE NEEDED BY 2230Z ACROSS THE REGION. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT MOVING SSEWD ACROSS NRN MS WITH DEWPOINTS NEAR 70 F JUST SOUTH OF THE BOUNDARY. THE HIGH SFC DEWPOINTS AND TEMPERATURES NEAR 90 F ARE RESULTING IN STRONG INSTABILITY. THIS COMBINED WITH A WEAKENING CAPPING INVERSION WILL ALLOW STORMS TO INITIATE AND SPREAD SSEWD THIS EVENING. ALTHOUGH FORECAST SOUNDINGS SHOW MID-LEVEL WINDS OF 30 KT...SUBSTANTIAL DIRECTIONAL SHEAR EXISTS BELOW 700 MB WHICH SHOULD BE SUFFICIENT FOR SUPERCELL DEVELOPMENT. STEEP MID-LEVEL LAPSE RATES NEAR 8.0 C/KM WILL BE FAVORABLE FOR LARGE HAIL. IN ADDITION...TEMP-DEWPOINT SPREADS OF GREATER THAN 20 DEGREES F WILL ENHANCE THE WIND DAMAGE POTENTIAL WITH THE STRONGER SUPERCELLS AND MORE WELL-DEVELOPED LINE SEGMENTS. ..BROYLES.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MOB...MEG...JAN... 34119007 34468917 34418843 33718741 33038711 32448701 32188780 32118867 32428940 32959020 33489031 33689029 WWWW From Mcd at goshenarc.org Wed Apr 19 22:14:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 18:14:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192212 SWOMCD SPC MCD 192212 TXZ000-200015- MESOSCALE DISCUSSION 0569 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT WED APR 19 2006 AREAS AFFECTED...NCENTRAL/NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 192212Z - 200015Z ISOLATED STORMS OVER CENTRAL TX /SW OF THE DFW METRO AREA/ MAY INTENSIFY AND BECOME SVR AS THEY MOVE ENEWD ACROSS NCENTRAL/NERN TX /AND INTO WRN PORTIONS OF WW 209/ OVER THE NEXT FEW HRS. LARGE HAIL SHOULD BE THE PRIMARY THREAT. WE ARE CONTINUING TO MONITOR TRENDS FOR A POSSIBLE WW. RECENT SAT OBS INDICATES THAT ELEVATED MOISTURE /CENTERED AROUND THE 850 MB LAYER/ WAS BEGINNING TO ADVANCE MORE RAPIDLY NORTH OF A SFC FRONTAL BOUNDARY THAT HAS BEGUN TO RETREAT NWD OVER CENTRAL TX. AS THIS MOISTURE MOVES NWD...IT SHOULD BEGIN TO ERODE THE MID LEVEL CAPPING INVERSION CENTERED AROUND 3 KM AND AID IN AN INTENSIFICATION PROCESS WITH THE CLUSTER OF STORMS MOVING OUT OF SWRN TX. FCST SOUNDINGS INDICATE THAT GIVEN THIS SCENARIO AROUND 2000 J/KG OF MUCAPE WILL BE REALIZED BY THESE STORMS OVER NCENTRAL/NERN TX. GIVEN 40-45 KTS OF CLOUD BEARING SHEAR...AN INCREASING SVR HAIL THREAT WOULD THUS OCCUR. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...FWD... 33249467 32769717 32569790 32359873 32129881 31499838 31469761 31609668 32119513 32329445 32959425 WWWW From Mcd at goshenarc.org Wed Apr 19 22:55:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 18:55:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 192253 SWOMCD SPC MCD 192253 TXZ000-200100- MESOSCALE DISCUSSION 0570 NWS STORM PREDICTION CENTER NORMAN OK 0553 PM CDT WED APR 19 2006 AREAS AFFECTED...SWRN/CENTRAL TX CONCERNING...SEVERE THUNDERSTORM WATCH 211... VALID 192253Z - 200100Z THREAT FOR SVR STORMS WILL LIKELY REMAIN LOW FOR MOST OF WW 211 FOR THE NEXT 1-2 HRS /THROUGH 00Z/. HOWEVER THE SVR THREAT IS ANTICIPATED TO INCREASE / ESPECIALLY OVER WRN/NRN PORTIONS OF WW 211 THEREAFTER/. A LARGE CIRRUS CANOPY ASSOCIATED WITH SVR TSTM CLUSTER OVER NRN COAHUILA MX HAS STABILIZED MUCH OF THE MIDDLE RIO GRANDE VALLEY EWD INTO THE EDWARDS PLATEAU REGION. THIS IS EVIDENT BY A 5-7 DEG COOLING TREND NOTED IN RECENT SFC OBS FROM DRT AND ECU. CONVECTION ON THE NRN EXTENSION OF THE HIGHER TERRAIN OF NRN COAHUILA /AND NORTH OF THE LARGE CIRRUS SHIELD/ MAY BE THE FIRST TO POSE A RENEWED SVR THREAT AS IT MOVES INTO NRN VAL VERDE...CROCKETT AND SUTTON COUNTIES IN THE NEXT FEW HRS. A GREATER SVR THREAT IS ANTICIPATED WITH SUPERCELL THUNDERSTORMS NOW MOVING INTO THE LOWER ELEVATIONS OF NRN COAHUILA MX AS THEY MAINTAIN THEMSELVES AND MOVE INTO SRN MAVERICK COUNTY /AROUND 01Z/. FURTHER NORTH...ELEVATED SVR POTENTIAL WILL LIKELY INCREASE AFTER 00Z OVER THE NRN EDWARDS PLATEAU/CONCHO VALLEY REGION AS ISENTROPIC LIFT STRENGTHENS NORTH OF A SLOWLY MOVING WARM FRONT. ..CROSBIE.. 04/19/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT... 31520019 30780115 29920121 28510116 29739801 31909807 WWWW From Mcd at goshenarc.org Thu Apr 20 00:33:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:33:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200031 SWOMCD SPC MCD 200031 TXZ000-200230- MESOSCALE DISCUSSION 0571 NWS STORM PREDICTION CENTER NORMAN OK 0731 PM CDT WED APR 19 2006 AREAS AFFECTED...LOWER-MIDDLE RIO GRANDE RIVER VALLEY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200031Z - 200230Z CLUSTER OF SVR STORMS OVER NERN COAHUILA MX WILL CONTINUE TO MOVE EWD AROUND 20-25 KTS AND ENTER WEBB AND DIMMIT COUNTIES AROUND 02Z. THREAT FOR LARGE HAIL AND DMGG WINDS APPEAR LIKELY IF STORMS CAN MAINTAIN INTENSITY BEFORE ENCOUNTERING STRONGER INHIBITION FURTHER EAST. 00Z DRT/BRO SOUNDINGS INPUT WITH OBSERVATION AT LRD INDICATES A EXTREMELY UNSTABLE AIRMASS WITH MLCAPES IN EXCESS OF 4000 J/KG. CLUSTER OF SVR STORMS /WITH SUPERCELL STRUCTURE/ OVER NERN COAHUILA MX WILL MOVE EWD AND SHOULD CROSS THE RIO GRANDE AROUND 02Z. GIVEN THE AIRMASS IN PLACE OVER THE MIDDLE-LOWER RIO GRANGE RIVER VALLEY..IT IS ANTICIPATED THAT A SVR THREAT WILL CONTINUE INTO THIS AREA. HOWEVER...FURTHER EAST...CINH WAS HIGHER AND SHOULD CONTINUE TO INCREASE WITH BOUNDARY LAYER COOLING THIS EVENING. THUS THE SVR THREAT IS NOT ANTICIPATED TO BE MUCH GREATER THAN A 3-5 COUNTY AREA SOUTH OF WW 211. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CRP...EWX...BRO... 29079962 28700010 27779989 27219925 27559888 28079875 29209910 WWWW From Mcd at goshenarc.org Thu Apr 20 00:44:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:44:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200041 SWOMCD SPC MCD 200041 MSZ000-ARZ000-LAZ000-TXZ000-200215- MESOSCALE DISCUSSION 0572 NWS STORM PREDICTION CENTER NORMAN OK 0741 PM CDT WED APR 19 2006 AREAS AFFECTED...NERN/ECENTRAL TX...NRN LA AND SRN AR CONCERNING...SEVERE THUNDERSTORM WATCH 209... VALID 200041Z - 200215Z THREAT FOR SVR APPEARS TO BE LOW FOR THE REMAINDER OF WW 209 VALID TIME /02Z/. HOWEVER...GIVEN THE LOW PROBABILITY THAT STILL REMAINS AND MODERATE INSTABILITY NO CLEARANCE OF WW 209 APPEARS WARRANTED ATTM. 00Z SHV SOUNDING SHOWED A NEARLY UNCAPPED MODERATELY UNSTABLE PROFILE WITH MLCAPES AROUND 2500 J/KG. THE PASSAGE OF A WEAK SHORTWAVE AND ELEVATED CONVECTION HAS NOW LEFT MOST OF WW 209 IN A REGION OF NEUTRAL FORCING. ALONG WITH THIS...THE SYNOPTIC BOUNDARY THAT WAS ONCE ALONG THE AR/LA BORDER HAS GRADUALLY LIFTED NWD AND IS NOW ALONG THE FAR NRN EDGE OF WW 209 ACROSS SRN AR. GIVEN LIMITED REMAINING HEATING AND WEAK CONVERGENCE ALONG THIS BOUNDARY NEW TSTM DEVELOPMENT APPEARS UNLIKELY TO OCCUR. FURTHER WEST...ELEVATED CONVECTION /REF 00Z FWD SOUNDING/ IN A MODERATELY UNSTABLE ENVIRONMENT /MUCAPES AROUND 2000 J/KG/ WILL LIKELY NOT MOVE INTO WW 209 UNTIL AFTER 02Z GIVEN RECENT OBSERVED CELL MOTIONS. HOWEVER GIVEN THE DEGREE OF INSTABILITY AND LIMITED CINH IN PLACE...IT IS POSSIBLE THAT THIS NCENTRAL TX CONVECTIVE ACTIVITY MAY STILL INTENSIFY AS IT MOVES EWD AND THUS A NEW WW MAY BE NEEDED FOR PORTIONS OF THE AREA AFTER 02Z. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...SHV...HGX...FWD... 33329472 32669545 30989538 31979116 33699119 33559374 WWWW From Mcd at goshenarc.org Thu Apr 20 00:53:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 20:53:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200051 SWOMCD SPC MCD 200051 GAZ000-FLZ000-ALZ000-200215- MESOSCALE DISCUSSION 0573 NWS STORM PREDICTION CENTER NORMAN OK 0751 PM CDT WED APR 19 2006 AREAS AFFECTED...AL...SW GA...NRN FL CONCERNING...TORNADO WATCH 210... VALID 200051Z - 200215Z A SEVERE THREAT WILL LIKELY CONTINUE ACROSS PARTS OF AL...SW GA AND NRN FL THROUGH MUCH OF THE EVENING. THE THREAT IN AL SHOULD GRADUALLY SHIFT SWWD ACROSS THE SE PART OF WW 213. ALTHOUGH THE AREA ACROSS ERN AL AND WRN GA WILL CONTINUE TO BE MONITORED...IT APPEARS A NEW WATCH WILL NOT BE NECESSARY TO REPLACE WW 210. A LARGE COMPLEX OF MOSTLY ELEVATED STORMS IS CURRENTLY ONGOING IN NCNTRL AL JUST BEHIND THE COOL SIDE OF A FRONTAL BOUNDARY. THE FRONTAL BOUNDARY AIDED BY THUNDERSTORM OUTFLOW IS MOVING WWD EVIDENT ON WSR-88D. AS THE BOUNDARY MOVES INTO CNTRL AL...NEW CONVECTIVE DEVELOPMENT SHOULD OCCUR WITH THE ONGOING MCS DRIFTING SLOWLY SSWWD ACROSS THE SERN PART OF WW 213. FORECAST SOUNDINGS SUGGEST THE INSTABILITY AND SHEAR ENVIRONMENT WILL CONTINUE TO REMAIN SUPPORTIVE OF SEVERE STORMS ALTHOUGH A GRADUAL DECREASE IN THE SEVERE WEATHER COVERAGE ACROSS CNTRL AL AND SWRN GA/NRN FL WILL LIKELY OCCUR AS INSTABILITY SLOWLY DECREASES THIS EVENING. ..BROYLES.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...HUN...MOB... 30878551 31908695 32838792 33318798 33848766 33928695 33618652 32928587 31658411 31298391 31008396 30598436 30618489 WWWW From Mcd at goshenarc.org Thu Apr 20 01:32:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 19 Apr 2006 21:32:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200130 SWOMCD SPC MCD 200130 TXZ000-200230- MESOSCALE DISCUSSION 0574 NWS STORM PREDICTION CENTER NORMAN OK 0830 PM CDT WED APR 19 2006 AREAS AFFECTED...NRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200130Z - 200230Z SEVERE STORMS WITH LARGE HAIL ARE EXPECTED TO INCREASE IN COVERAGE THROUGH THE EVENING. A WW MAY BE REQUIRED. STORMS CONTINUE TO INCREASE N OF WARM FRONT IN WARM ADVECTION ZONE. VERY STEEP LAPSE RATES ARE IN PLACE WITH STRONG ELEVATED INSTABILITY. IN ADDITION...EFFECTIVE DEEP LAYER SHEAR VECTORS ARE FAVORABLE FOR ORGANIZED SEVERE CONVECTION. GIVEN CONTINUING WARM ADVECTION...STORMS WILL LIKELY PERSIST FOR SEVERAL HOURS. ..JEWELL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...SJT...LUB...MAF... 31840189 32850151 33270041 33489746 33309648 32049607 31479672 31669983 31470161 WWWW From Mcd at goshenarc.org Thu Apr 20 07:46:23 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 03:46:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200744 SWOMCD SPC MCD 200743 TXZ000-200845- MESOSCALE DISCUSSION 0575 NWS STORM PREDICTION CENTER NORMAN OK 0243 AM CDT THU APR 20 2006 AREAS AFFECTED...W CNTRL THROUGH PARTS OF WRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 214... VALID 200743Z - 200845Z SEVERE THUNDERSTORM WATCH 214 WILL PROBABLY NEED TO BE REPLACED BY ANOTHER WW BY 08Z. STORMS ARE EXPECTED TO CONTINUE AND MAY DEVELOP FARTHER W LATER THIS MORNING. PRIMARY THREATS WILL BE LARGE HAIL. EARLY THIS MORNING...A SELY LOW LEVEL JET AROUND 30 KT WILL PERSIST ACROSS S CNTRL THROUGH WRN TX. THIS WILL CONTINUE TO ADVECT HIGHER THETA-E AIR NWWD WITH TIME BENEATH STEEP MID LEVEL LAPSE RATES. STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE OF LIFT WHERE THE LOW LEVEL JET IS INTERSECTING THE OUTFLOW BOUNDARY. WV IMAGERY SHOWS A SHORTWAVE TROUGH MOVING EWD THROUGH NM. DEEP LAYER ASCENT ASSOCIATED WITH THIS FEATURE AND LIFT ASSOCIATED WITH THE SELY LOW LEVEL JET MAY CONTRIBUTE TO THUNDERSTORM DEVELOPMENT LATER THIS MORNING AS THE ATMOSPHERE DESTABILIZES FARTHER W. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...SJT...MAF... 32349831 31950077 31760231 32440247 32920175 32860005 32769831 WWWW From Mcd at goshenarc.org Thu Apr 20 09:24:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 05:24:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200922 SWOMCD SPC MCD 200922 TNZ000-KYZ000-ILZ000-MOZ000-ARZ000-201115- MESOSCALE DISCUSSION 0576 NWS STORM PREDICTION CENTER NORMAN OK 0422 AM CDT THU APR 20 2006 AREAS AFFECTED...EXTREME NERN AR THROUGH WRN TN...NRN PARTS OF MIDDLE TN AND SWRN KY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 200922Z - 201115Z THREAT FOR PRIMARILY ISOLATED HAIL WILL EXIST WITH STRONGER STORMS DEVELOPING OVER PARTS OF WRN TN AND SWRN KY. AREA WILL CONTINUE TO BE MONITORED. STORMS ARE EXPECTED TO CONTINUE DEVELOPING WITHIN ZONE OF WEAK WARM ADVECTION ALONG A MODEST 20 TO 25 KT LOW LEVEL JET FROM WRN THROUGH MIDDLE TN AND INTO WRN AND CNTRL KY. THE ATMOSPHERE IN THIS REGION IS MODERATELY UNSTABLE WITH MID LEVEL 700 TO 500 MB LAPSE RATES FROM 7.5C TO 8C. VWP DATA SHOW EFFECTIVE VERTICAL SHEAR ONLY MARGINALLY SUPPORTIVE OF ORGANIZED SUSTAINED STORM STRUCTURES...AND DOMINANT STORM TYPE WILL MOST LIKELY BE MULTICELLS. HOWEVER...THE THERMODYNAMIC ENVIRONMENT APPEARS SUPPORTIVE OF HAIL WITH THE STRONGER STORMS. OTHER STORMS OVER NERN AR APPEAR TO HAVE DEVELOPED A COLD POOL AND ARE FORWARD PROPAGATING. STRONG WIND GUSTS AS WELL AS HAIL MAY ACCOMPANY THIS ACTIVITY AS IT MOVES TOWARD WRN TN. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...OHX...PAH...MEG... 36118578 35308891 35158992 36078988 37458817 37608571 WWWW From Mcd at goshenarc.org Thu Apr 20 09:57:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 05:57:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 200955 SWOMCD SPC MCD 200955 TXZ000-201100- MESOSCALE DISCUSSION 0577 NWS STORM PREDICTION CENTER NORMAN OK 0455 AM CDT THU APR 20 2006 AREAS AFFECTED...SWRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 217... VALID 200955Z - 201100Z LONE STORM REMAINS OVER SWRN TX JUST S OF DEL RIO. THIS STORM MAY STILL BE CAPABLE OF PRODUCING HAIL. HOWEVER...IT IS EXPECTED TO GRADUALLY DIMINISH...AND ADDITIONAL DEVELOPMENT IS NOT ANTICIPATED. WW 217 SHOULD BE ABLE TO BE CANCELLED ONCE THIS STORM DISSIPATES. STORMS THAT DEVELOPED OVER THE HIGHER TERRAIN OF MEXICO HAVE MOSTLY DISSIPATED AS THEY CROSSED INTO SWRN TX...MOST LIKELY AS A RESULT OF ENCOUNTERING STRONGER CONVECTIVE INHIBITION. THE OBSERVED 00Z RAOB FROM DEL RIO AND FORECAST RUC SOUNDING DATA SHOW AN INVERSION ASSOCIATED WITH THE EML IN THE 850 MB TO 700 MB LAYER...AND ADDITIONAL DEVELOPMENT IS NOT ANTICIPATED THROUGH THE EARLY MORNING. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 30139975 28369965 28450116 30000109 WWWW From Mcd at goshenarc.org Thu Apr 20 11:10:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 07:10:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201106 SWOMCD SPC MCD 201106 ARZ000-201300- MESOSCALE DISCUSSION 0578 NWS STORM PREDICTION CENTER NORMAN OK 0606 AM CDT THU APR 20 2006 AREAS AFFECTED...CNTRL AND SRN AR THROUGH NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 216... VALID 201106Z - 201300Z THREAT FOR ISOLATED HAIL EXPECTED TO PERSIST MAINLY ACROSS PARTS OF CNTRL AR NEXT COUPLE HOURS. SKELETAL OUTFLOW BOUNDARY IS SHIFTING SEWD THROUGH NRN LA AND LATEST OBJECTIVE ANALYSIS SHOWS STRONGER CAP IN THIS REGION...WHICH SHOULD CONTINUE TO LIMIT DEVELOPMENT ALONG THIS PORTION OF THE BOUNDARY. FARTHER N...ELEVATED STORMS ARE INCREASING IN COVERAGE WITHIN ZONE OF ASCENT DOWNSTREAM FROM MCV THAT IS MOVING THROUGH NERN TX AND SWRN AR. THE ATMOSPHERE IN THIS REGION REMAINS MODERATELY UNSTABLE WITH STEEP MID LEVEL LAPSE RATES AND SHOULD CONTINUE TO SUPPORT A THREAT FOR HAIL AS STORMS DEVELOP NEXT 2-3 HOURS. ..DIAL.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV... 33829137 33769324 34999336 35209161 WWWW From Mcd at goshenarc.org Thu Apr 20 15:18:22 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 11:18:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201516 SWOMCD SPC MCD 201515 TXZ000-201615- MESOSCALE DISCUSSION 0579 NWS STORM PREDICTION CENTER NORMAN OK 1015 AM CDT THU APR 20 2006 AREAS AFFECTED...W TX CONCERNING...SEVERE THUNDERSTORM WATCH 218...219... VALID 201515Z - 201615Z CONTINUE WW 219. PARTS OF WW 218 MAY BE EXTENDED LOCALLY ANOTHER COUPLE OF HOURS. MAIN UPSTREAM SOUTHERN BRANCH IMPULSE IS JUST NOW PROGRESSING INTO THE SOUTHERN ROCKIES...AND ZONE OF STRONGER ISENTROPIC ASCENT IS EXPECTED TO PERSIST FROM AREAS EAST OF THE TEXAS BIG BEND INTO WEST CENTRAL TEXAS INTO EARLY AFTERNOON. THIS EXTENDS FROM JUST NORTH OF STALLED SURFACE FRONT...NEAR/SOUTH OF THE DEL RIO/SAN ANTONIO AREAS ...INTO THE VICINITY OF STRONGER MID-LEVEL BAROCLINIC ZONE ACROSS NORTH CENTRAL TEXAS. THOUGH NOT STRONG...SOUTHERLY LOW-LEVEL JET IS TRANSPORTING HIGH PRECIPITABLE WATER AIR MASS NORTHWARD OUT OF THE LOWER RIO GRANDE VALLEY...CONTRIBUTING TO CAPE OF 1000-2000 J/KG ABOVE FRONTAL INVERSION ACROSS WEST TEXAS. MOST VIGOROUS STORMS...WITH LARGEST HAIL POTENTIAL...SEEM LIKELY TO REMAIN FOCUSED IN CLOSER PROXIMITY TO FRONT...NORTH/NORTHEAST OF DEL RIO THROUGH 18Z. HOWEVER...MORE MARGINAL SEVERE HAIL THREAT MAY BE SLOW TO DIMINISH IN AREAS TO THE NORTH.. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT...LUB...MAF... 30170182 30950250 31750256 32570207 33100112 33170055 33209995 32859941 32539889 32029915 31259985 30639964 30129947 29639986 29610053 29930147 WWWW From Mcd at goshenarc.org Thu Apr 20 16:21:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:21:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411 WWWW From Mcd at goshenarc.org Thu Apr 20 16:27:27 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:27:27 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455 WWWW From Mcd at goshenarc.org Thu Apr 20 16:28:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:28:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411  From Mcd at goshenarc.org Thu Apr 20 16:29:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:29:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455  From Mcd at goshenarc.org Thu Apr 20 16:31:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:31:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201619 SWOMCD SPC MCD 201619 GAZ000-ALZ000-MSZ000-201745- MESOSCALE DISCUSSION 0580 NWS STORM PREDICTION CENTER NORMAN OK 1119 AM CDT THU APR 20 2006 AREAS AFFECTED...NRN/CENTRAL MS...NRN/CENTRAL AL...NRN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201619Z - 201745Z ON THE SRN FRINGE OF AN UPPER WAVE MOVING ACROSS TN...CONVECTION MAY CONTINUE TO DEVELOP AND INTENSIFY ALONG AN OUTFLOW BOUNDARY OVER NRN MS/NRN AL AND AN ADDITIONAL BOUNDARY OVER NWRN GA OVER THE NEXT FEW HRS. SLIGHTLY GREATER INSTABILITY AND SHEAR OVER THIS AREA WILL SUPPORT A POTENTIALLY MORE SIGNIFICANT HAIL THREAT. A WW MAY BE REQUIRED SOON FOR PARTS OF THE AREA. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM GLH TO TUP IN NRN MS...ENEWD TO FAR NRN AL. AN ADDITIONAL BOUNDARY IS NOTED OVER FAR NERN AL/NWRN GA. WEAKER DEEP LAYER SHEAR WAS EVIDENT OVER ALL OF THIS AREA THAN IS PRESENT FURTHER NORTH...WITH AREA VWP/S INDICATING AROUND 30 KTS OF MID LEVEL FLOW AS OPPOSED TO THE 40-50 KTS OF FLOW OVER TN AND NRN AR. HOWEVER...STRONGER FLOW WILL CONTINUE TO APPROACH THE AREA FORM THE SW AHEAD OF ANOTHER UPPER WAVE OVER THE ARKLATEX. MODERATE INSTABILITY EXISTED OVER THIS AREA WITH STEEP MID LEVEL LAPSE RATES /7.5-8 DEG C/KM/ NOTED ON BMX AND SHV 12Z SOUNDINGS. MAIN QUESTION REMAINS HOW MUCH CAN THE BOUNDARY LAYER DESTABILIZE AND REMOVE REMAINING CINH OVER NRN MS/AL GIVEN EXTENSIVE MID-HIGH LEVEL CLOUDS CURRENTLY IN PLACE OR MOVING INTO THE AREA. ASSUMING SUFFICIENT ADDITIONAL HEATING DOES OCCUR...FOCUSED CONVERGENCE ALONG AFOREMENTIONED OUTFLOW BOUNDARIES SHOULD RESULT IN ADDITIONAL SVR TSTM DEVELOPMENT ACROSS NRN MS/AL AND NWRN GA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...BMX...HUN...MEG...JAN... 34948535 34748795 34588818 33799062 33589067 33269092 32459031 32898701 33148549 33858421 34838411  From Mcd at goshenarc.org Thu Apr 20 16:32:00 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 12:32:00 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201625 SWOMCD SPC MCD 201624 WVZ000-VAZ000-NCZ000-OHZ000-TNZ000-KYZ000-GAZ000-201830- MESOSCALE DISCUSSION 0581 NWS STORM PREDICTION CENTER NORMAN OK 1124 AM CDT THU APR 20 2006 AREAS AFFECTED...ERN TN...ERN KY...SRN OH...W VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201624Z - 201830Z A WW IS NOT ANTICIPATED...BUT TRENDS ARE BEING MONITORED. MOST UNSTABLE CAPE OF 1000 TO 2000 J/KG CONTINUES TO SUPPORT SCATTERED VIGOROUS THUNDERSTORM ACTIVITY ACROSS THE LOWER OHIO/ TENNESSEE VALLEY. ACTIVITY STILL APPEARS MOSTLY BASED ABOVE LINGERING RADIATIONAL INVERSION LAYER...SUPPORTED BY BROAD ZONE OF LOW-LEVEL WARM ADVECTION AHEAD OF MID-LEVEL IMPULSE LIFTING OUT OF THE LOWER MISSISSIPPI VALLEY. PERHAPS AIDED BY INCREASINGLY DIVERGENT UPPER FLOW FIELD...ACTIVITY SEEMS TO BE EVOLVING INTO AN INCREASINGLY ORGANIZED CONVECTIVE SYSTEM ACROSS KENTUCKY/TENNESSEE ...WHICH WILL CONTINUE INTO THE CENTRAL APPALACHIANS DURING THE 18-20Z TIME FRAME. CUT-OFF FROM GULF MOISTURE RETURN...BOUNDARY LAYER DEW POINTS ARE NOT LIKELY TO INCREASE SIGNIFICANTLY ACROSS THE CENTRAL APPALACHIANS. THIS WILL LIMIT MAGNITUDE OF DESTABILIZATION THIS AFTERNOON. HOWEVER...WITH ADDITIONAL INSOLATION...WEAK SURFACE BASED DESTABILIZATION SEEMS LIKELY TO MAINTAIN CONVECTIVE DEVELOPMENT. LOW-LEVEL THERMODYNAMIC ENVIRONMENT WILL BECOME INCREASING FAVORABLE FOR GUSTY SURFACE WINDS THAT MAY APPROACH SEVERE LIMITS...IN ADDITION TO CONTINUING RISK OF MARGINALLY SEVERE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...RLX...GSP...MRX...JKL...ILN...LMK...OHX... 38528483 39238460 39478267 39238134 38338071 37038059 36368105 35408230 34988328 35188457 35698469 36188472 37278438 38178455  From Mcd at goshenarc.org Thu Apr 20 18:23:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:23:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201821 SWOMCD SPC MCD 201821 TXZ000-201945- MESOSCALE DISCUSSION 0582 NWS STORM PREDICTION CENTER NORMAN OK 0121 PM CDT THU APR 20 2006 AREAS AFFECTED...PARTS OF WRN AND CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 219...220... VALID 201821Z - 201945Z HAIL THREAT WILL CONTINUE ACROSS WW AREAS ANOTHER COUPLE OF HOURS ...BUT MAXIMUM HAIL SIZES MAY BEGIN TO DECREASE AS ACTIVITY DEVELOPS TOWARD NORTH CENTRAL/NORTHEAST TEXAS. NEW WWS NORTH/EAST OF 219/220 MAY NOT BE NEEDED. DRY LINE ACROSS SOUTHWEST TEXAS WILL BE MONITORED FOR POSSIBILITY OF INCREASING SEVERE THREAT LATER THIS AFTERNOON. PRIMARY SOUTHERN BRANCH SHORT WAVE TROUGH IS NOW CROSSING THE SOUTHERN ROCKIES...BUT WEAKER DOWNSTREAM IMPULSE APPEARS TO HAVE LIFTED THROUGH THE TEXAS BIG BEND/PECOS VALLEY REGION. MID/UPPER FORCING WITH THIS FEATURE SEEMS LIKELY TO SPREAD NORTHEAST OF THE EDWARDS PLATEAU AND HILL COUNTRY BETWEEN NOW AND 21Z...ACCOMPANIED BY STRONGER CONVECTIVE DEVELOPMENT. MODELS SUGGEST...HOWEVER...THAT THE LOW-LEVEL JET WILL REMAIN DIRECTED NORTHWESTWARD THROUGH THE LOWER RIO GRANDE VALLEY INTO THE PECOS VALLEY. WITH LOSS OF BETTER MOIST INFLOW...ONGOING CONVECTION SEEMS LIKELY TO BECOME INCREASINGLY ELEVATED AS IT PROGRESSES DEEPER INTO CENTRAL TEXAS...AND WEAKER CAPE MAY MITIGATE LARGE HAIL THREAT. AS CONVECTION LIFTS NORTHWARD...MOIST BOUNDARY LAYER WILL BEGIN TO WARM FROM SOUTH CENTRAL TEXAS INTO THE TRANSPECOS REGION...AND SURFACE FRONT MAY REDEVELOP NORTHWARD...CLOSER TO MIDLAND/JUNCTION AND AUSTIN. HOWEVER...STRENGTHENING CAP MAY INHIBIT FURTHER CONVECTIVE DEVELOPMENT UNTIL FORCING WITH UPSTREAM SHORT WAVE BEGINS TO INTERACT WITH DRY LINE ACROSS SOUTHWEST TEXAS LATER THIS AFTERNOON. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX...SJT...LUB...MAF... 32360261 33090168 33209964 33309800 33309667 32549541 31029570 30119771 29829870 30310038 30690162 30210198 29910221 30040266 31350285 WWWW From Mcd at goshenarc.org Thu Apr 20 18:41:21 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:41:21 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201839 SWOMCD SPC MCD 201838 TNZ000-GAZ000-ALZ000-MSZ000-LAZ000-ARZ000-202045- MESOSCALE DISCUSSION 0583 NWS STORM PREDICTION CENTER NORMAN OK 0138 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN...NRN/CENTRAL MS CONCERNING...SEVERE THUNDERSTORM WATCH 221... VALID 201838Z - 202045Z CONTINUE ALL OF WW 221. WEAK SURFACE CONVERGENCE COMBINED WITH MID/HIGH CLOUD COVER ARE LIKELY THE MAIN INHIBITING FACTORS FOR NEW DEEP CONVECTIVE DEVELOPMENT OVER NRN AL/SRN MIDDLE TN. HOWEVER...A FEW MORE HRS OF HEATING AND LIKELY CLEARING OF SOME OF THE CLOUD COVER SHOULD AID IN A GREATER POTENTIAL FOR SVR TSTM DEVELOPMENT OVER WW 221 BY MID-AFTERNOON. FURTHER WEST...A WELL DEFINED MCV ON SAT IMAGERY OVER THE ARKLATEX WAS MOVING QUICKLY NEWD. AHEAD OF THIS FEATURE...AN OUTFLOW BOUNDARY WAS WELL DEFINED EXTENDING FROM SERN AR ENEWD INTO NRN MS. OBJECTIVE ANALYSIS INDICATES THAT THE AIRMASS OVER MUCH OF NRN/CENTRAL MS HAS LITTLE REMAINING CINH. WITH THE FOCUSED CONVERGENCE ALONG THE BOUNDARY AND APPROACHING UPPER SUPPORT...SCT CONVECTION MAY DEVELOP OVER NRN/CENTRAL MS IN THE NEXT FEW HRS. MODERATE INSTABILITY AND SHEAR IN PLACE OVER THE AREA WOULD SUPPORT A SVR THREAT WITH ANY TSTMS. THUS...A NEW WW MAY BE NEEDED WEST OF WW 221 IN THE NEXT HOUR OR SO. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN... 35068784 35648756 35598481 34458526 33068577 32918872 32929108 33459119 34499034 WWWW From Mcd at goshenarc.org Thu Apr 20 18:56:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 14:56:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201853 SWOMCD SPC MCD 201853 NCZ000-SCZ000-TNZ000-GAZ000-202100- MESOSCALE DISCUSSION 0584 NWS STORM PREDICTION CENTER NORMAN OK 0153 PM CDT THU APR 20 2006 AREAS AFFECTED...NERN GA...WRN NC AND UPSTATE SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 201853Z - 202100Z CONVECTION WAS GRADUALLY INTENSIFYING OVER FAR SERN TN/NWRN GA UNDER THE INFLUENCE OF AN UPPER WAVE MOVING ACROSS TN AND ON THE NRN END OF INSTABILITY AXIS. WE WILL MONITOR TRENDS FOR ANY INCREASING SVR THREAT OVER THIS AREA...BUT A WW IS NOT EXPECTED ATTM. 18Z SOUNDING FROM ATLANTA SHOWS STEEP LOW-MID LEVEL LAPSE RATES WITH MARGINAL INSTABILITY /MUCAPES AROUND 1000 J/KG /. CONVECTION RECENTLY STRENGTHENING OVER NWRN GA AND SERN TN WAS IN AN AXIS WHERE DEWPTS AND INSTABILITY WHERE SLIGHTLY HIGHER. GIVEN THE SOMEWHAT ORGANIZED NATURE OF THE CONVECTION IT IS POSSIBLE THAT DESPITE SOMEWHAT WEAKER INSTABILITY OVER NERN GA...WRN NC/UPSTATE SC THERE MAY BE SOME MARGINAL SVR HAIL/WIND THREAT THAT DEVELOPS WITH THIS ACTIVITY AS IT MOVES INTO THIS AREA IN THE NEXT FEW HRS. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC... 36038242 35738357 35298429 35008455 34678466 34228430 34138395 34128331 34778234 35598163 WWWW From Mcd at goshenarc.org Thu Apr 20 20:00:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:00:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 201958 SWOMCD SPC MCD 201958 TXZ000-202100- MESOSCALE DISCUSSION 0585 NWS STORM PREDICTION CENTER NORMAN OK 0258 PM CDT THU APR 20 2006 AREAS AFFECTED...SW THRU CNTRL TX CONCERNING...SEVERE THUNDERSTORM WATCH 219...220... VALID 201958Z - 202100Z SEVERE WEATHER WATCHES WILL LIKELY BE REPLACED WITH A NEW TORNADO WATCH BEFORE 21Z. SOUTHERN STREAM SHORT WAVE TROUGH IS FINALLY BEGINNING TO PROGRESS EAST OF THE SOUTHERN ROCKIES...AND LEADING EDGE OF STRONGER MID-LEVEL COOLING IS ALREADY OVERSPREADING THE TRANS PECOS REGION. THIS...IN CONJUNCTION WITH CONTINUED WARMING OF BOUNDARY LAYER SOUTH OF OUTFLOW ENHANCED SURFACE FRONT...IS CONTRIBUTING TO WEAKENING INHIBITION. MIXED LAYER CAPE ALONG/SOUTH OF FRONT IS CURRENTLY IN EXCESS OF 1500 J/KG...AND WILL INCREASE FURTHER THROUGH THE REMAINDER OF THE AFTERNOON. DRY LINE/FRONTAL INTERSECTION SHIFTING FROM SOUTH OF MIDLAND THROUGH THE JUNCTION AREA BETWEEN 20/21-21/00Z SEEMS MOST PROBABLE FOCUS FOR INTENSE SURFACE BASED CONVECTIVE DEVELOPMENT. WIND PROFILES EXHIBITING PRONOUNCED VEERING WITH HEIGHT IN LOWER-LEVELS WILL BE FAVORABLE FOR SUPERCELLS...PARTICULARLY AS 50 KT 500 MB SPEED MAXIMUM NOSES ACROSS SOUTHWEST TEXAS. RISK OF TORNADOES IS EXPECTED TO INCREASE...ALONG WITH CONTINUING THREAT FOR LARGE HAIL. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...EWX...SJT...MAF... 31000221 31830226 31750099 31340038 31299959 31239871 30679771 29649824 29369952 29920118 30400237 WWWW From Mcd at goshenarc.org Thu Apr 20 20:44:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:44:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202041 SWOMCD SPC MCD 202040 GAZ000-NCZ000-TNZ000-ALZ000-MSZ000-202245- MESOSCALE DISCUSSION 0586 NWS STORM PREDICTION CENTER NORMAN OK 0340 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL...SRN MIDDLE TN AND NRN/WRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 221... VALID 202040Z - 202245Z GREATEST SVR THREAT FOR THE NEXT FEW HRS OVER WW 221 WILL BE ACROSS CENTRAL/SERN PORTIONS OF WW 221 / CENTRAL AND NERN AL / WITH CLUSTER OF STG-SVR STORMS ONGOING. THREAT FOR SVR APPEARS TO BE MOST MARGINAL OVER THE NEXT 1-2 HRS ACROSS SRN MIDDLE TN AS MID LEVEL SUBSIDENCE AND COOLER OUTFLOW AIR REDUCES RENEWED CONVECTIVE POTENTIAL. LATEST SFC ANALYSIS SHOWS AN OUTFLOW BOUNDARY EXTENDING FROM SOUTH OF TUP TO NEAR BHM TO NERN AL/NWRN GA. SVR STORMS HAD DEVELOPED OVER CENTRAL/NERN AL IN REGION OF STRONGEST LOW LEVEL CONVERGENCE IN THE VICINITY OF A MESOLOW TO THE NORTH OF THE BHM AREA. MODERATE INSTABILITY EAST OF THIS ACTIVITY OVER WCENTRAL GA SUGGESTS THAT THE SVR THREAT SHOULD EXTEND EAST OF WW 221. CURRENT STORM MOTIONS WOULD TAKE THE SVR THREAT WITH THIS CLUSTER INTO FAR ECENTRAL AL/WCENTRAL GA BEGINNING AROUND 22Z. THE SVR THREAT SHOULD NOT DEVELOP EWD ACROSS ALL OF NRN GA...AS AN N-S ORIENTED BOUNDARY EXTENDING JUST EAST OF THE ATLANTA METRO AREA SWD TO NEAR MCN SHOULD REMAIN IN PLACE THROUGH THE EVENING HOURS. A WW MAY BE NEEDED FOR NRN GA SHORTLY. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...OHX...BMX...HUN...MEG... 35478481 35488795 34998808 32908830 32938495 33008379 34978339 35008496 WWWW From Mcd at goshenarc.org Thu Apr 20 20:57:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 16:57:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202054 SWOMCD SPC MCD 202054 TXZ000-NMZ000-202200- MESOSCALE DISCUSSION 0587 NWS STORM PREDICTION CENTER NORMAN OK 0354 PM CDT THU APR 20 2006 AREAS AFFECTED...ERN NM...PARTS OF SW TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 202054Z - 202200Z TRENDS ARE BEING MONITORED FOR POSSIBILITY OF A WW. INSOLATION AND MID-LEVEL COOLING...ASSOCIATED WITH SOUTHERN STREAM TROUGH...HAVE CONTRIBUTED TO VERY STEEP LAPSE RATES ACROSS MUCH OF EASTERN NEW MEXICO. BOUNDARY LAYER IS RATHER DRY...BUT DEEPLY MIXED AND SUFFICIENTLY UNSTABLE FOR CONVECTIVE DEVELOPMENT. ACTIVITY HAS INITIATED ALONG WAVE/OUTFLOW PROPAGATING WESTWARD OUT OF ONGOING CONVECTION ACROSS THE TEXAS SOUTH PLAINS. LOW-LEVEL THERMAL RIDGE AXIS EAST OF THE MOUNTAINS IS ALSO BECOMING FOCUS FOR ACTIVITY IN RESPONSE TO MID-LEVEL FORCING. TENDENCY SHOULD BE FOR STRONGER CONVECTION TO EVENTUALLY DEVELOP SOUTH/SOUTHEASTWARD ALONG EFFECTIVE SURFACE FRONT INTO AREAS WEST OF MIDLAND LATE THIS AFTERNOON. SHEAR IN CLOUD BEARING LAYER SEEMS SUFFICIENT FOR UPDRAFT ROTATION...WHICH MAY ENHANCE RISK OF MARGINALLY SEVERE HAIL...DESPITE LIMITED CAPE. OTHERWISE...DAMAGING WIND GUSTS WILL ALSO BE POSSIBLE IN STRONGEST CELLS. ..KERR.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MAF...ABQ...EPZ... 36520494 35560442 34250395 33550390 32850346 32300311 32000282 31410304 31620401 32780537 34480597 WWWW From Mcd at goshenarc.org Thu Apr 20 21:18:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 17:18:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202116 SWOMCD SPC MCD 202115 ALZ000-TNZ000-MSZ000-ARZ000-LAZ000-202315- MESOSCALE DISCUSSION 0588 NWS STORM PREDICTION CENTER NORMAN OK 0415 PM CDT THU APR 20 2006 AREAS AFFECTED...SERN AR...NRN MS AND SWRN TN CONCERNING...SEVERE THUNDERSTORM WATCH 222... VALID 202115Z - 202315Z TSTMS HAVE HAD TROUBLE SUSTAINING THEMSELVES ACROSS WW 222 OVER THE LAST FEW HRS. HOWEVER...THERE REMAINS A CONTINUED THREAT FOR REDEVELOPMENT OVER THE REGION AS ASCENT REMAINS AHEAD OF WEAK VORT MAX OVER AR AND SURFACE OUTFLOW BOUNDARY AIDS IN SURFACE CONVERGENCE. STORMS THAT DEVELOPED EARLIER OVER THE MS RIVER VALLEY HAVE SINCE DISSIPATED. HOWEVER SFC ANALYSIS SHOWS A MESOLOW OVER SERN AR...AND NEW CONVECTIVE DEVELOPMENT SHOULD CONTINUE TO OCCUR IN THIS REGION. ISOLATED DEVELOPMENT WILL ALSO REMAIN POSSIBLE ALONG AN OUTFLOW BOUNDARY EXTENDING FROM JUST NORTH OF GLH TO CBM. THERMODYNAMIC/SHEAR PARAMETERS REMAIN FAVORABLE FOR A SVR THREAT FOR ANY STORM THAT CAN BE SUSTAINED. ADDITIONALLY...THERE IS SOME POTENTIAL FOR AN ISOLATED SVR STORM TO DEVELOP NORTH OF WW 222 ACROSS SWRN TN WHERE DIFFERENTIAL HEATING BOUNDARY APPEARS TO EXIST. HOWEVER WEAKER INSTABILITY SUGGESTS THAT THE SVR THREAT IN THIS AREA SHOULD REMAIN LIMITED AND ANOTHER WW IS NOT ANTICIPATED. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HUN...MEG...JAN...LZK...SHV... 34978811 35558820 35918902 35019031 34819050 34199220 32949245 33038996 33098838 WWWW From Mcd at goshenarc.org Thu Apr 20 22:56:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 18:56:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202254 SWOMCD SPC MCD 202254 TXZ000-210030- MESOSCALE DISCUSSION 0589 NWS STORM PREDICTION CENTER NORMAN OK 0554 PM CDT THU APR 20 2006 AREAS AFFECTED...SE TX CONCERNING...SEVERE THUNDERSTORM WATCH 223... VALID 202254Z - 210030Z AN MCS IS CURRENTLY ORGANIZING OVER SCNTRL TX JUST EAST OF THE AUSTIN AREA. AS THE COMPLEX MOVES SLOWLY EWD...THE SEVERE THREAT SHOULD INCREASE EAST OF WW 223. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT EXTENDING SWWD FROM NE TX ACROSS THE TX HILL COUNTRY. DEWPOINTS AHEAD OF THE FRONT ARE IN THE MID 60S F WITH AN AXIS OF MODERATE INSTABILITY LOCATED FROM SOUTH TX EXTENDING NNEWD JUST AHEAD OF THE BOUNDARY. AS THE BOUNDARY MOVES SEWD AND A SHORTWAVE-TROUGH APPROACHES FROM THE WEST...CONVECTIVE COVERAGE SHOULD INCREASE ALLOWING THE MCS TO CONTINUE EWD ACROSS SE TX THIS EVENING. OBJECTIVE ANALYSIS CURRENTLY SHOWS A 55 KT MID-LEVEL JET OVER CNTRL TX MOVING EWD. THIS FEATURE WILL BEGIN TO AFFECT SE TX SUSTAINING VERTICAL SHEAR PROFILES SUFFICIENT FOR SEVERE STORMS. HOWEVER...INSTABILITY WILL LIKELY REMAIN WEAKER OVER SE TX KEEPING THE SEVERE THREAT ISOLATED WITH HAIL AND WIND DAMAGE BEING THE PRIMARY THREATS. ..BROYLES.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...EWX... 29169724 29919769 30439746 30699659 30959560 30299485 29339563 WWWW From Mcd at goshenarc.org Thu Apr 20 23:14:32 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 19:14:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 202312 SWOMCD SPC MCD 202311 GAZ000-NCZ000-TNZ000-ALZ000-MSZ000-210115- MESOSCALE DISCUSSION 0590 NWS STORM PREDICTION CENTER NORMAN OK 0611 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN AL AND NRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 221...225... VALID 202311Z - 210115Z THREAT FOR SVR WILL CONTINUE WITH ORGANIZED CLUSTER ACROSS MUCH OF WW 225 OVER THE NEXT SEVERAL HRS AS IT MOVES INTO THE WRN PORTION OF THE ATL METRO AREA BETWEEN 00-01Z. FURTHER WEST...SVR THREAT SHOULD GRADUALLY DIMINISH OVER WW 221 IN THE NEXT 1-3 HRS. THUS A NEW WW TO REPLACE WW 221 IS NOT LIKELY ATTM...ALTHOUGH LOCAL WFO EXTENSION IS POSSIBLE. LATEST SFC ANALYSIS SHOWS A WELL DEFINED COLD POOL HAS DEVELOPED OVER NERN AL ASSOCIATED WITH SVR TSTM CLUSTER MOVING OUT OF WW 221 INTO WW 225 /NWRN GA/. GIVEN ORGANIZED NATURE OF CONVECTION AND STEEP LOW LEVEL LAPSE RATES /NOTED ON THE 18Z ATL SOUNDING / DMGG WINDS MAY BECOME THE GREATER SVR THREAT AS ACTIVITY MOVES TOWARDS THE ATL METRO AREA. IN THE WAKE OF THIS CLUSTER...SSWLY FLOW OF 10-20 KTS /NOTED ON RECENT BMX VWP DATA/ WAS ORTHOGONAL TO THE OUTFLOW BOUNDARY OVER CENTRAL/NCENTRAL AL. COMBINED WITH MODERATE INSTABILITY AND MARGINAL CINH THIS SHOULD SUPPORT A THREAT FOR REDEVELOPMENT OF TSTMS TO THE EAST OF THE OUTFLOW BOUNDARY OVER NCENTRAL/NERN AL FOR THE NEXT COUPLE OF HRS. GRADUALLY DIMINISHING INSTABILITY AFTER 00Z /WITH LOSS OF HEATING / COMBINED WITH DISPLACEMENT OF CONVECTION FURTHER AWAY FROM THE WWD MOVING OUTFLOW BOUNDARY /NOTED ON BMX RADAR/ WILL LIKELY LEAD TO A DIMINISHING SVR THREAT WITH TIME. THE DIMINISHING INSTABILITY SHOULD ALSO LEAD TO A GRADUAL DEMISE OF ISOLATED SVR STORM NEAR THE AL/MS BORDER...BUT NOT BEFORE THE PASSAGE OF THE WWD MOVING OUTFLOW BOUNDARY INTERACTS WITH THIS STORM. LOCALLY BACKED LOW LEVEL FLOW JUST AHEAD OF THE BOUNDARY MAY AID IN A BRIEF LOCALIZED TORNADO THREAT WITH THIS STORM AROUND 00Z. ..CROSBIE.. 04/20/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...BMX...HUN...MEG...JAN... 35158506 34678822 33368850 33298603 33068613 33008428 34998343 34988503 WWWW From Mcd at goshenarc.org Fri Apr 21 00:38:19 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 20:38:19 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210035 SWOMCD SPC MCD 210035 ALZ000-MSZ000-ARZ000-LAZ000-210200- MESOSCALE DISCUSSION 0591 NWS STORM PREDICTION CENTER NORMAN OK 0735 PM CDT THU APR 20 2006 AREAS AFFECTED...SERN AR...NRN MS CONCERNING...SEVERE THUNDERSTORM WATCH 222... VALID 210035Z - 210200Z SVR TSTM THREAT APPEARS TO BE VERY LOW DURING THE REMAINING VALID PORTIONS OF WW 222 THROUGH THE REST OF THE WATCH VALID TIME /02Z/. WILL KEEP PORTIONS OF SERN AR/NRN MS IN THE WW 222 UNTIL THEN IN CASE NEW DEVELOPMENT OCCURS. 00Z JAN SOUNDING SHOWED AN INVERSION CENTERED AROUND 700 MB THAT IS LIKELY PART OF THE REASON CONVECTION HAS FAILED TO BE SUSTAINED OVER MUCH OF WW 222 THIS AFTERNOON/EARLY EVENING. WITH LIMITED CONVERGENCE...WEAK LOW LEVEL WINDS /REF 00Z SHV AND JAN SOUNDINGS/ AND DECREASING INSTABILITY WITH NIGHTFALL...IT IS A VERY LOW PROBABILITY THAT NEW SVR TSTM DEVELOPMENT WILL OCCUR BEFORE 02Z. HOWEVER...SHORT TERM MODELS INDICATE THAT AS UPPER SYSTEM MOVES OUT OF ERN TX...WAA WILL INCREASE. GIVEN RELATIVELY LIMITED CINH OVER NRN LA /PER THE 00Z SHV SOUNDING/ NEW SVR TSTM DEVELOPMENT MAY INCREASE LATER TONIGHT. HOWEVER THIS IS ANTICIPATED TO OCCUR WELL AFTER 02Z...SO WW 222 WILL LIKELY BE ALLOWED TO EXPIRE. ..CROSBIE.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MEG...JAN...LZK... 34908830 34229181 32969174 32898964 33158822 WWWW From Mcd at goshenarc.org Fri Apr 21 00:57:55 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 20:57:55 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210055 SWOMCD SPC MCD 210055 GAZ000-SCZ000-NCZ000-TNZ000-ALZ000-210300- MESOSCALE DISCUSSION 0592 NWS STORM PREDICTION CENTER NORMAN OK 0755 PM CDT THU APR 20 2006 AREAS AFFECTED...NRN GA CONCERNING...SEVERE THUNDERSTORM WATCH 225... VALID 210055Z - 210300Z SVR THREAT SHOULD NOT EXTEND MUCH EAST OF WW 225 ACROSS NERN GA AND THUS A NEW WW IS NOT EXPECTED. SVR WIND/HAIL THREAT WILL BE MAINLY CONFINED OVER ERN/SRN PORTIONS OF WW 225 FOR THE NEXT 1-2 HRS. HOWEVER ELEVATED TSTMS WITH MARGINALLY SVR HAIL MAY OCCUR WEST OF THIS CONVECTIVE LINE OVER NWRN GA. RADAR IMAGERY SHOWS A WELL DEFINED CONVECTIVE LINE MOVING THROUGH NRN GA /INCLUDING THE ATL METRO AREA/. STEEP LOW LEVEL LAPSE RATES WILL SUPPORT THE THREAT FOR DMGG WINDS WITH THIS LINE FOR THE NEXT 1-2 HRS AS IT MOVES THROUGH THE REMAINDER OF WW 225. THERE MAY BE A MARGINAL SVR THREAT JUST EAST OF WW 225...BUT AREAL EXTENT OF MODEST INSTABILITY SHOULD BE LIMITED TO ONLY A 1-2 ROWS OF COUNTIES EAST OF WW 225 AS STABLE AIR REMAINS OVER NERN/ECENTRAL GA SUPPORTED BY ELY LOW LEVEL FLOW. FURTHER WEST...ALTHOUGH AIRMASS IS WORKED OVER ACROSS NWRN GA BEHIND THE CONVECTIVE LINE...INCREASING LOW LEVEL SSWLY WINDS ATOP MESO-HIGH OVER NWRN GA MAY SUPPORT A MARGINAL HAIL THREAT FOR THE NEXT FEW HRS WITH ANY ADDITIONAL NEW TSTM DEVELOPMENT. THIS AREA MAY BE CLEARED FROM WW 225 BY 02Z IF NEW TSTM INITIATION FAILS TO OCCUR BEFORE THEN. ..CROSBIE.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...BMX...HUN... 34998531 33028612 33038414 33138323 34988316 WWWW From Mcd at goshenarc.org Fri Apr 21 02:34:31 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 22:34:31 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210231 SWOMCD SPC MCD 210231 TNZ000-MSZ000-MOZ000-ARZ000-TXZ000-210400- MESOSCALE DISCUSSION 0593 NWS STORM PREDICTION CENTER NORMAN OK 0931 PM CDT THU APR 20 2006 AREAS AFFECTED...WRN TN / FAR NW MS / MUCH OF AR CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 210231Z - 210400Z STORMS ARE EXPECTED TO INCREASE IN COVERAGE THROUGH THE EVENING HOURS AND OVERNIGHT...WITH A THREAT OF SOME SVR HAIL. A WW COULD BE REQUIRED SOON. LATEST UPPER AIR ANALYSIS AS WELL AS OBJECTIVE ANALYSIS SHOWS 700 MB TEMPERATURE GRADIENT ACROSS NRN MS INTO SRN AR / NRN LA. ALTHOUGH MODERATELY UNSTABLE SOUTH OF THIS LINE...CAPPING EXISTS AS SEEN ON 00Z JAN SOUNDING AS WELL AS TAMDAR DATA ACROSS CENTRAL MS...DECREASING TO THE NORTH WITH NO CAP ON COOL SIDE OF BOUNDARY FROM WRN TN ACROSS FAR NRN MS AND INTO CENTRAL AR. MODERATE WARM ADVECTION ALONG WITH APPROACHING UPPER VORT ASSOCIATED WITH E TX CONVECTION WILL LIKELY ALLOW FOR AN INCREASE IN STORMS ACROSS THE MCD AREA. ISOLATED TO SCATTERED SVR HAIL WILL BE THE MAIN THREAT. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...MEG...JAN...LZK...SHV... 33709124 34268958 35008829 35388715 36558711 36458834 36219006 35039267 34249411 33669420 33289369 33289259 WWWW From Mcd at goshenarc.org Fri Apr 21 03:56:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Thu, 20 Apr 2006 23:56:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210354 SWOMCD SPC MCD 210353 ALZ000-TNZ000-MSZ000-210530- MESOSCALE DISCUSSION 0594 NWS STORM PREDICTION CENTER NORMAN OK 1053 PM CDT THU APR 20 2006 AREAS AFFECTED...CENTRAL AND NRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 228... VALID 210353Z - 210530Z SEVERE THREAT APPEARS TO BE DECREASING AS OF 330Z ACROSS MUCH OF WW 228...HOWEVER...ADDITIONAL DEVELOPMENT MAY OCCUR LATER THIS EVENING INTO THE EARLY MORNING HOURS OVER NWRN AL. LARGE HAIL WOULD BE THE MAIN SVR THREAT. ISOLATED STORMS PERSIST WITHIN WARM ADVECTION ZONE LYING NW-SE ACROSS AL. MOST OF THE AIRMASS E OF THIS BOUNDARY HAS BEEN AFFECTED BY COOL OUTFLOW INTO NERN AL AND NWRN GA...THUS STORMS HAVE SHOWN WEAKENING TRENDS AS THEY MOVE NEWD. AREA WIND PROFILERS/VWPS DO SHOW INCREASING LOW LEVEL FLOW /850 MB/ AROUND 15-20 KTS WHICH WILL CONTINUE TO FEED STORMS ALONG THE WARM FRONTAL/OUTFLOW BOUNDARY FOR SEVERAL MORE HOURS...ALTHOUGH COMBINATION OF CONTINUED WARM ADVECTION ALOFT WITH COOLING BOUNDARY LAYER WILL LIKELY CAUSE STORMS TO EVENTUALLY DIE OVER CENTRAL AND ERN AL. GREATER THREAT FOR SVR EXIST ACROSS NWRN AL...IN CLOSER PROXIMITY TO INSTABILITY POOL NOW OVER NRN MS. APPROACHING UPPER WAVE WILL CAUSE STORMS TO INCREASE TO THE WEST OF WW 228 OVER THE NEXT SEVERAL HOURS...AND A FEW OF THESE STORMS MAY MAKE IT INTO NWRN AL LATER TONIGHT WITH A LARGE HAIL THREAT. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG... 34998815 35008685 33568632 32648621 32488664 33008825 WWWW From Mcd at goshenarc.org Fri Apr 21 04:29:36 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 00:29:36 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210427 SWOMCD SPC MCD 210426 LAZ000-TXZ000-210600- MESOSCALE DISCUSSION 0595 NWS STORM PREDICTION CENTER NORMAN OK 1126 PM CDT THU APR 20 2006 AREAS AFFECTED...EAST TX/NRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 227... VALID 210426Z - 210600Z A MARGINAL SEVERE THREAT WILL LIKELY CONTINUE ACROSS THE ERN PART OF WW 227 OVER THE NEXT FEW HOURS. THE SEVERE THREAT MAY EXPAND INTO NRN LA AS THE MCS DRIFTS EWD OVERNIGHT. SFC ANALYSIS CURRENTLY SHOWS A COLD FRONT MOVING SEWD ACROSS EAST TX WITH A MOIST AXIS EXTENDING NWD THROUGH THE SABINE RIVER VALLEY INTO NW LA. SFC DEWPOINTS ALONG THE MOIST AXIS ARE IN THE MID TO UPPER 60S F AND THIS IS HELPING TO MAINTAIN MODERATE INSTABILITY ACROSS WRN AND CNTRL LA. IN ADDITION...REGIONAL PROFILERS SHOW 40-45 KT OF 0-6 KM SHEAR SUGGESTING THE SHEAR AND INSTABILITY MAY BE ENOUGH FOR A MARGINAL SEVERE THREAT OVERNIGHT. HAIL AND STRONG WIND GUSTS WOULD BE LIKELY WITH THE STRONGER CELLS AS THE MCS MOVES INTO NRN AND CNTRL LA AFTER 06Z. ..BROYLES.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LCH...SHV...HGX... 30339389 30419480 30789528 31389526 32379418 32749254 32139154 31019235 WWWW From Mcd at goshenarc.org Fri Apr 21 05:06:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 01:06:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210504 SWOMCD SPC MCD 210504 ALZ000-TNZ000-MSZ000-210700- MESOSCALE DISCUSSION 0596 NWS STORM PREDICTION CENTER NORMAN OK 1204 AM CDT FRI APR 21 2006 AREAS AFFECTED...NERN MS / SWRN TN / EXTREME NWRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210504Z - 210700Z THREAT FOR WIND DAMAGE AND/OR ISOLATED TORNADOES APPEARS TO BE INCREASING. LARGE HAIL THREAT MAY BE ENHANCED AS WELL. LATEST RADAR SHOWS ROTATION DEVELOPING WITH CELLS OVER NRN MS / SWRN TN. SURFACE ANALYSIS INDICATES LOWER 70S TEMPERATURES INTO NRN MS...WHICH WHEN COMBINED WITH MID 60S DEWPOINTS YIELDS SURFACE BASED PARCELS WITH LITTLE CIN IN MODERATELY UNSTABLE ENVIRONMENT. FURTHER...AREA VAD WIND PROFILES ARE SHOWING STRONGER LOW LEVEL SHEAR THAN CURRENTLY ANALYZED BY RUC. WHILE THEY MAY BE A LITTLE TOO STRONG WHEN COMPARED TO LOCAL ACARS/TAMDAR SOUNDINGS...IT APPEARS AT LEAST 20-25 KT VEERING LOW LEVEL FLOW EXIST OFF THE SURFACE WHICH IS RESULTING IN 0-1 SRH VALUES IN EXCESS OF 250 M2/S2. THUS...AN ISOLATED TORNADO CANNOT BE RULED OUT...WITH THE MAIN LIMITING FACTOR BEING SURFACE DECOUPLING AS REFLECTED IN WEAK SURFACE WIND SPEEDS OF 5 KTS OR LESS. A POTENTIAL SIGN OF INCREASED TORNADO THREAT MAY BE AN INCREASE IN SURFACE WINDS AHEAD OF STORMS AND WITHIN RELATIVELY WARMER / 70S / TEMPERATURES. ..JEWELL.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG...JAN... 33859016 34349025 34958944 35298897 35448815 35248788 34538789 34128817 WWWW From Mcd at goshenarc.org Fri Apr 21 06:14:45 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 02:14:45 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210612 SWOMCD SPC MCD 210612 TXZ000-210815- MESOSCALE DISCUSSION 0597 NWS STORM PREDICTION CENTER NORMAN OK 0112 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS CENTRAL/S-CENTRAL TX. CONCERNING...SEVERE THUNDERSTORM WATCH 230... VALID 210612Z - 210815Z TSTMS CONTINUE TO INCREASE IN COVERAGE ACROSS PORTIONS CENTRAL/S-CENTRAL TX -- FROM NERN HILL COUNTRY W ACT...SWWD ACROSS HILL COUNTRY AND LOWLANDS NE DRT. ALTHOUGH ANY OF THIS ACTIVITY MAY PRODUCE HAIL AS IT MOVES EWD AND SEWD INTO MORE UNSTABLE INFLOW...MAIN SEVERE POTENTIAL WILL BE CONCENTRATED ACROSS AREA BETWEEN AUS-COT...INCLUDING SAT. WW 230 IS THEREFORE REQUIRED. SFC MESOANALYSIS INDICATES QUASISTATIONARY BAROCLINIC ZONE FROM ABOUT 20 S DRT....ENEWD THROUGH HDO...SAT...IAH. THIS BOUNDARY HAS BEEN REINFORCED BY OUTFLOWS FROM EARLIER CONVECTION. CONVECTION DEVELOPING/INCREASING IN COVERAGE TO ITS N DOES NOT APPEAR TO BE SFC-BASED...GIVEN STATIC STABILITY APPARENT NEAR SFC IN MODIFIED RAOBS AND RUC FCST SOUNDINGS. HOWEVER...COMBINATION OF STEEP MIDLEVEL LAPSE RATES -- APPARENT ON 00Z DRT RAOB -- AND LOW LEVEL WAA/MOIST ADVECTION ATOP STABLE LAYER -- CONTRIBUTES TO FAVORABLE BUOYANCY. ELEVATED MUCAPES 1000-1500 J/KG ARE EVIDENT WITHIN ABOUT 70-90 NM OF BOUNDARY...DECREASING GRADUALLY FARTHER NWD OVER CENTRAL TX. EFFECTIVE SHEAR VECTOR SPEEDS OF 40-60 KT SUGGEST SOME POTENTIAL FOR SUPERCELL STRUCTURES...ESPECIALLY OVER S-CENTRAL TX VICINITY SAT...WHICH WOULD ENHANCE LARGE HAIL POTENTIAL. TSTMS MOVING ALONG AND S OF BOUNDARY WILL BE NEARLY SFC-BASED...AND MAY PRODUCE DAMAGING WIND AS WELL. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...CRP...EWX...SJT... 29100080 29900037 30429949 31079837 30999775 30609688 30339662 29839657 29029698 28519861 28000001 28140006 28250026 28480035 28670048 28930062 29060065 WWWW From Mcd at goshenarc.org Fri Apr 21 07:18:26 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 03:18:26 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210716 SWOMCD SPC MCD 210715 TNZ000-GAZ000-ALZ000-MSZ000-ARZ000-LAZ000-210915- MESOSCALE DISCUSSION 0598 NWS STORM PREDICTION CENTER NORMAN OK 0215 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS SRN/ERN AR...NRN LA...NRN MS...TN...NRN AL...NWRN GA. CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210715Z - 210915Z WW SHOULD BE CONTINUED ALONG/NE OF LA/AR MCS. AREAS SE AND E OF WW ARE BEING MONITORED FOR POSSIBILITY OF ADDITIONAL WW. ORGANIZED COMPLEXES OF STRONG-SEVERE TSTMS CONTINUE TO MOVE ACROSS SWRN PORTIONS WW...FROM E-CENTRAL AR TO N-CENTRAL LA -- AND ALSO ACROSS ERN PORTIONS WRN-MIDDLE TN. MAIN THREAT CONTINUES TO BE HAIL...ALTHOUGH OCCASIONAL DAMAGING GUSTS ARE POSSIBLE ACROSS SERN AR...NERN LA AND NWRN MS GIVEN NEARLY SFC-BASED INFLOW LAYERS EVIDENT IN MODIFIED RUC SOUNDINGS. RUC WIND PROFILES IN LOW LEVELS APPEAR TOO WEAK ACROSS NRN MS COMPARED TO OBSERVED VWP...WITH RADAR DERIVED 0-1 KM SRH REACHING 300-400 J/KG RANGE AND OBSERVED 0-6 KM AGL SHEAR AROUND 50 KT. THIS WILL FAVOR SUPERCELL STRUCTURES AND CONTINUED RISK OF LARGE HAIL. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY FROM EARLIER MCS...FROM MCN...20 W BHM...20 WNW MSL. THIS BOUNDARY HAS BECOME QUASISTATIONARY. ISOLATED TO WIDELY SCATTERED TSTMS HAVE DEVELOPED FROM AL/TN BORDER AREA ENEWD ALMOST TO TYS. THIS ACTIVITY IS OCCURRING IN ZONE OF ELEVATED LOW LEVEL WAA AND MOIST ADVECTION...WELL N OF SFC OUTFLOW BOUNDARY. AS ELEVATED AIR MASS CONTINUES TO DESTABILIZE NEWD ACROSS SRN-MIDDLE TN...ERN TN AND EXTREME NWRN GA...CONVECTIVE COVERAGE SHOULD CONTINUE TO INCREASE. NEITHER EFFECTIVE SHEAR NOR ELEVATED BUOYANCY SHOULD BE AS LARGE AS FARTHER W IN WW...HOWEVER OCCASIONAL SEVERE HAIL IS POSSIBLE FROM THIS ACTIVITY AS IT MOVES NEWD 20-25 KT. ISOLATED TSTMS PRODUCED HAIL TO NEAR .88 INCH DIAMETER INVOF TCL...WITH LEFT SPLIT MOVING NNEWD ACROSS AREA BETWEEN TCL-HSV. ALTHOUGH AIR MASS HAS DIABATICALLY STABILIZED IN SKIN LAYER NEAR SFC...EFFECTIVE LIFTED PARCELS STILL ARE SFC-BASED...AMIDST ENOUGH DEEP-LAYER SHEAR TO SUPPORT BOTH SUPERCELLS AND ORGANIZED MULTICELLS. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...OHX...BMX...HUN...MEG...JAN...LZK...SHV... 32299338 33049253 34809148 36598573 36458455 35678404 34658485 33648609 33248759 34488754 WWWW From Mcd at goshenarc.org Fri Apr 21 09:21:44 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 05:21:44 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210913 SWOMCD SPC MCD 210913 TXZ000-211115- MESOSCALE DISCUSSION 0599 NWS STORM PREDICTION CENTER NORMAN OK 0413 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/SE TX. CONCERNING...SEVERE THUNDERSTORM WATCH 230... VALID 210913Z - 211115Z QUASI-LINEAR CONVECTIVE COMPLEX HAS EVOLVED FROM PREVIOUSLY BROKEN BAND OF DISCRETE CELLS AND...AS OF 845Z...EXTENDED FROM SRN FRINGES SAT METRO AREA NEWD TO NRN BRAZOS COUNTY. MOST VIGOROUS CONVECTION SHOULD CROSS AREA FROM VCT THROUGH HOU. ALTHOUGH A FEW ELEVATED TSTMS MAY DEVELOP OVER REINFORCING OUTFLOW POOL...SEVERE THREAT SHOULD BE RELATIVELY MEAGER WITH SUCH ACTIVITY...AND WW MAY BE CLEARED FROM NW-SE AS MCS MOVES BY. PROSPECTIVE PATH OF MCS -- TOWARD MIDDLE-UPPER TX COAST -- MAY REQUIRE WW SOON. AIR MASS AHEAD OF THESE TSTMS...ACROSS SE TX...APPEARS FAVORABLE FOR MCS TO MOVE GENERALLY ESEWD DURING NEXT FEW HOURS...PRODUCING OCCASIONAL HAIL. DAMAGING GUSTS ALSO ARE POSSIBLE IN MIDDLE-SRN PORTION OF MCS...WHERE NEAR-SFC STABLE LAYER IS SHALLOWEST...AND MOST PENETRABLE BY STRONG-SEVERE DOWNDRAFTS. SFC MESOANALYSIS SHOWS QUASISTATIONARY BAROCLINIC BOUNDARY FROM NEAR SABINE/NEWTON COUNTY LINE WSWWD NEAR IAH...THEN APPROXIMATELY 50 N VCT...BEFORE BEING OVERTAKEN BY SRN PORTION OF MCS. MODIFIED RUC SOUNDINGS SHOW LIFTED PARCELS S OF BOUNDARY ARE SFC-BASED OR NEARLY SO. HOWEVER...THESE PARCELS ARE RESTRICTED FROM ASCENT BY CAPPING IN 750-850 MB LAYER...WHICH INCREASES WITH SRN EXTENT. LLJ HAS INCREASED TO 40 KT S OF MCS...PER CRP VWP TRENDS. MCS MAY BACKBUILD SLGTLY AMIDST FAVORABLE STORM-RELATIVE INFLOW AND MUCAPES AROUND 1500 J/KG. HOWEVER...ANTICIPATE MAJORITY OF ACTIVITY WILL RESULT FROM FORCED ASCENT TO LFC...ALONG THAT PORTION OF OUTFLOW EDGE IN AND S OF SFC FRONTAL ZONE. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...CRP...EWX... 29209947 29429891 29749811 30259751 30649699 30799663 30509549 29649502 28729562 28109671 28009752 28399917 28529971 28610000 28830010 28920006 29029989  From Mcd at goshenarc.org Fri Apr 21 09:39:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 05:39:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 210936 SWOMCD SPC MCD 210936 TNZ000-ALZ000-MSZ000-211100- MESOSCALE DISCUSSION 0600 NWS STORM PREDICTION CENTER NORMAN OK 0436 AM CDT FRI APR 21 2006 AREAS AFFECTED...NRN MS...WRN PORTIONS OF WRN AND MIDDLE TN...NW AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 210936Z - 211100Z MAIN THREAT FOR ISOLATED SEVERE HAIL/WIND SHOULD BE FOCUSED ACROSS FAR NRN MS WHERE OUTFLOW FROM W MERGES WITH E-W BOUNDARY JUST N OF THE TN BORDER. HOWEVER...INSTABILITY IS EXPECTED TO GRADUALLY DIMINISH THROUGH THE MORNING...AND THE OVERALL SEVERE THREAT MAY DIMINISH TO THE POINT THAT ANOTHER WW IS NOT NECESSARY. ONE MCS WITH A WEAK BOW STRUCTURE IS MOVING ENEWD INTO NW MS...WHILE OTHER CONVECTION CONTINUES ALONG A DIFFUSE E-W BOUNDARY ACROSS SRN PORTIONS OF WRN AND MIDDLE TN. THE WRN MCS SHOULD CONTINUE ACROSS NRN MS FOR THE NEXT COUPLE OF HOURS...WITH THE THREAT FOR SPORADIC HAIL AND STRONG WIND GUSTS. HOWEVER...THE ERN PROGRESS OF THE STRONGER STORMS MAY BE LIMITED LATER THIS MORNING BY GRADUALLY DIMINISHING INSTABILITY OVER NRN AL AND MIDDLE TN. GIVEN THE WEAKENING TRENDS NOTED IN RADAR/SATELLITE IMAGERY...AND THE FORECAST OF DIMINISHING INSTABILITY WITH TIME...AN ADDITIONAL SEVERE THUNDERSTORM WATCH MAY NOT BE NEEDED AFTER WW 229 EXPIRES AT 10Z. ..THOMPSON.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...OHX...BMX...HUN...JAN... 35478933 35628928 33808928 33959006 34429018 35099004 35498957 35668827 35588700 35338665 34728656 34348669 33908767 WWWW From Mcd at goshenarc.org Fri Apr 21 10:03:03 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 06:03:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211000 SWOMCD SPC MCD 211000 COR ALZ000-TNZ000-MSZ000-211100- MESOSCALE DISCUSSION 0600 NWS STORM PREDICTION CENTER NORMAN OK 0500 AM CDT FRI APR 21 2006 AREAS AFFECTED...NRN MS...WRN PORTIONS OF WRN AND MIDDLE TN...NW AL CONCERNING...SEVERE THUNDERSTORM WATCH 229... VALID 211000Z - 211100Z CORRECTED FOR SPURIOUS LINE SEGMENT MAIN THREAT FOR ISOLATED SEVERE HAIL/WIND SHOULD BE FOCUSED ACROSS FAR NRN MS WHERE OUTFLOW FROM W MERGES WITH E-W BOUNDARY JUST N OF THE TN BORDER. HOWEVER...INSTABILITY IS EXPECTED TO GRADUALLY DIMINISH THROUGH THE MORNING...AND THE OVERALL SEVERE THREAT MAY DIMINISH TO THE POINT THAT ANOTHER WW IS NOT NECESSARY. ONE MCS WITH A WEAK BOW STRUCTURE IS MOVING ENEWD INTO NW MS...WHILE OTHER CONVECTION CONTINUES ALONG A DIFFUSE E-W BOUNDARY ACROSS SRN PORTIONS OF WRN AND MIDDLE TN. THE WRN MCS SHOULD CONTINUE ACROSS NRN MS FOR THE NEXT COUPLE OF HOURS...WITH THE THREAT FOR SPORADIC HAIL AND STRONG WIND GUSTS. HOWEVER...THE ERN PROGRESS OF THE STRONGER STORMS MAY BE LIMITED LATER THIS MORNING BY GRADUALLY DIMINISHING INSTABILITY OVER NRN AL AND MIDDLE TN. GIVEN THE WEAKENING TRENDS NOTED IN RADAR/SATELLITE IMAGERY...AND THE FORECAST OF DIMINISHING INSTABILITY WITH TIME...AN ADDITIONAL SEVERE THUNDERSTORM WATCH MAY NOT BE NEEDED AFTER WW 229 EXPIRES AT 10Z. ..THOMPSON.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...BMX...HUN...MEG...JAN... 33808928 33959006 34429018 35099004 35498957 35668827 35588700 35338665 34728656 34348669 33908767 WWWW From Mcd at goshenarc.org Fri Apr 21 11:41:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 07:41:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211139 SWOMCD SPC MCD 211138 LAZ000-TXZ000-211345- MESOSCALE DISCUSSION 0601 NWS STORM PREDICTION CENTER NORMAN OK 0638 AM CDT FRI APR 21 2006 AREAS AFFECTED...PORTIONS SE TX...EXTREME SWRN LA CONCERNING...SEVERE THUNDERSTORM WATCH 231... VALID 211138Z - 211345Z ORGANIZED MCS/BOW WITH SMALLER EMBEDDED LEWP FEATURES WILL CONTINUE MOVING ESEWD ACROSS MID/UPPER TX COASTAL PLAIN. TSTMS SHOULD MOVE OFFSHORE ARANSAS/CALHOUN/MATAGORDA/BRAZORIA/GALVESTON COUNTIES BETWEEN 12Z-13Z...AND OFFSHORE CHAMBERS COUNTY BY ABOUT 14Z. MRGLLY SEVERE HAIL AND 50-52 KT GUSTS HAVE BEEN REPORTED WITH THIS ACTIVITY IN THE PAST 1-2 HOURS. POTENTIAL FOR DAMAGING GUSTS AND OCCASIONAL HAIL REMAINS WITH THIS MCS AS IT MOVES THROUGH FAVORABLY MOIST AIR MASS ALONG AND S OF QUASISTATIONARY BAROCLINIC ZONE...ANALYZED AT 11Z FROM NRN PORTIONS HOU METRO AREA NEWD PAST POE. CONVECTION WILL BE SUPPORTED BY SFC DEW POINTS LOW 70S F IN INFLOW LAYER...WITH SBCAPES 1500-2500 J/KG S OF BOUNDARY...AND STRONGLY FORCED ASCENT TO LFC ALONG LEADING PORTION OF OUTFLOW SLAB. KINEMATIC PROFILES REMAIN FAVORABLE WITH 100-200 J/KG OF 0-1 KM SRH...40-50 KT 0-6 KM SHEAR. NRN PORTION OF THIS COMPLEX MAY AFFECT PORTIONS HARDIN/JEFFERSON/ORANGE COUNTIES JUST E OF WW...AS WELL AS CAMERON PARISH. ..EDWARDS.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...HGX...CRP... 28829684 28769632 28989588 29339562 29709540 29979540 30269555 30369531 30119436 30019358 29759318 29449329 29179444 28299596 28279666 WWWW From Mcd at goshenarc.org Fri Apr 21 14:53:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 10:53:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211451 SWOMCD SPC MCD 211451 MSZ000-LAZ000-211615- MESOSCALE DISCUSSION 0602 NWS STORM PREDICTION CENTER NORMAN OK 0951 AM CDT FRI APR 21 2006 AREAS AFFECTED...ERN LA...CNTRL/SRN MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211451Z - 211615Z WW WILL PROBABLY BE ISSUED SHORTLY. FORCING ASSOCIATED WITH SOUTHERN BRANCH IMPULSE IS CONTRIBUTING TO MAINTENANCE OF MESOSCALE CONVECTIVE SYSTEM...AND THIS SEEMS LIKELY TO REMAIN THE CASE AS IT SPREADS INTO THE LOWER MISSISSIPPI VALLEY THROUGH THE MID DAY HOURS. BOUNDARY LAYER AHEAD OF THIS SYSTEM... AND SOUTH OF OLD OUTFLOW BOUNDARY EXTENDING ACROSS NORTHEASTERN LOUISIANA THROUGH CENTRAL MISSISSIPPI INTO NORTH CENTRAL ALABAMA...REMAINS MOIST...AND WILL BECOMING INCREASINGLY UNSTABLE WITH HEATING. MIXED LAYER CAPE IS EXPECTED TO INCREASE IN EXCESS OF 2000 J/KG...AND SEVERE THREAT SEEMS LIKELY TO INCREASE AS CONVERGENCE ALONG OUTFLOWS SUPPORT INCREASINGLY SURFACE BASED CONVECTIVE DEVELOPMENT. SOUTHERLY LOW-LEVEL JET IS STILL ONLY ON THE ORDER OF 20-25 KT... BUT APPEARS TO BE STRENGTHENING FROM SOUTH CENTRAL LOUISIANA INTO CENTRAL MISSISSIPPI. BENEATH 40+ KT CYCLONIC MID-LEVEL FLOW...THIS WILL PROVIDE FAVORABLY STRONG MEAN FLOW/SHEAR REGIME FOR DAMAGING WINDS. ISOLATED SUPERCELLS ARE ALSO POSSIBLE...WITH ENHANCED RISK OF LARGE HAIL...POSSIBLY TORNADOES. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LCH... 32569148 32779086 32849026 33098966 33188874 32218874 31758908 31098937 30498951 29938979 29708972 29499024 29449087 29699171 29789230 30029265 30449261 30979242 31339195 31839168 32169164 WWWW From Mcd at goshenarc.org Fri Apr 21 17:20:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 13:20:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211717 SWOMCD SPC MCD 211717 NCZ000-TNZ000-GAZ000-ALZ000-211845- MESOSCALE DISCUSSION 0603 NWS STORM PREDICTION CENTER NORMAN OK 1217 PM CDT FRI APR 21 2006 AREAS AFFECTED...NRN/CNTRL AL...ERN TN...NW GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211717Z - 211845Z SLOW INCREASE IN CONVECTIVE DEVELOPMENT IS ALREADY ONGOING. THIS SHOULD INTENSIFY FURTHER THIS AFTERNOON. TRENDS ARE BEING MONITORED FOR AN INCREASING SEVERE THREAT...AND THE POSSIBILITY OF A WW. INITIAL SOUTHERN BRANCH IMPULSE CONTINUES TO LIFT NORTHEASTWARD THROUGH THE UPPER TENNESSEE VALLEY. 50+ KT 500 MB JET STREAK SEEMS TO BE ACCOMPANYING THIS FEATURE...AND MAIN CONVECTIVE DEVELOPMENT ASSOCIATED WITH STRONGER MID-LEVEL FORCING IS BEGINNING TO SHIFT TOWARD THE UPPER OHIO VALLEY/NORTH CENTRAL APPALACHIANS. HOWEVER...IN WAKE OF THIS FEATURE...AND AHEAD OF LOWER MISSISSIPPI VALLEY SHORT WAVE TROUGH...CONFLUENT LOW-LEVEL REGIME MAY BECOME FOCUS FOR INCREASING THUNDERSTORM ACTIVITY INTO THE 19-20Z TIME FRAME. MOIST BOUNDARY LAYER FROM THE WESTERN SLOPES OF THE SOUTHERN APPALACHIANS INTO NORTHERN ALABAMA IS DEEPENING WITH INSOLATION. AS TEMPERATURES APPROACH THE LOWER 80S...MIXED LAYER CAPE IS EXPECTED TO EXCEED 1000 J/KG. THIS SHOULD BE SUFFICIENT FOR VIGOROUS UPDRAFTS IN FAVORABLY SHEARED ENVIRONMENT FOR MID-LEVEL UPDRAFT ROTATION. LARGE HAIL MAY BE PRIMARY SEVERE THREAT. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...MRX...FFC...OHX...BMX...HUN... 34998618 35658598 36368452 36338366 35578355 35378371 34358429 33538489 32768617 32358731 32538818 33158816 34138711 WWWW From Mcd at goshenarc.org Fri Apr 21 17:54:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 13:54:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211752 SWOMCD SPC MCD 211752 ALZ000-FLZ000-MSZ000-LAZ000-211915- MESOSCALE DISCUSSION 0604 NWS STORM PREDICTION CENTER NORMAN OK 1252 PM CDT FRI APR 21 2006 AREAS AFFECTED...SE LA...CNTRL/SRN MS...INTO CNTRL/SRN AL CONCERNING...SEVERE THUNDERSTORM WATCH 232... VALID 211752Z - 211915Z CONTINUE WW. CENTRAL/SOUTHERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE ARE BEING MONITORED FOR A POSSIBLE ADDITIONAL WW LATER THIS AFTERNOON CONGLOMERATE SURFACE COLD POOL IS PROGRESSING EAST OF THE NATCHEZ/ BATON ROUGE/LAFAYETTE AREAS. THIS FEATURE IS BECOMING A FOCUS FOR INTENSIFYING CONVECTION...WITH ADDITIONAL SCATTERED STORMS DEVELOPING/INCREASING IN COVERAGE AHEAD OF IT ACROSS MUCH OF CENTRAL/SOUTHERN MISSISSIPPI AND SOUTHEAST LOUISIANA. ACTIVITY IS NOW LIKELY BASED IN MOIST BOUNDARY LAYER...WHICH IS BECOMING INCREASINGLY UNSTABLE WITH CONTINUED INSOLATION. THIS AIR MASS EXTENDS EASTWARD THROUGH MUCH OF CENTRAL/SOUTHERN ALABAMA AND THE WESTERN FLORIDA PANHANDLE...WHERE CAPE MAY APPROACH 2000 J/KG BY PEAK HEATING. DESTABILIZATION AND FORCING/SHEAR ASSOCIATED UPSTREAM SOUTHERN BRANCH TROUGH/JET STREAK ARE EXPECTED TO SUPPORT CONTINUED EVOLUTION OF A LARGE CONVECTIVE CLUSTER. AS SURFACE COLD POOL STRENGTHENS... EASTWARD ACCELERATION ACROSS SOUTHERN MISSISSIPPI AT 30-40+ KT APPEARS POSSIBLE...ACCOMPANIED BY INCREASING THREAT FOR DAMAGING WINDS. GUST FRONT MAY ADVANCE EAST OF THE EASTERN MISSISSIPPI BORDER BY 21-22Z. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...MOB...JAN...LIX... 32489031 32998906 33018834 33078771 32778738 32338709 31798710 31228726 30838735 30188768 29758804 29428857 29088939 28969007 29089072 30419060 31009088 WWWW From Mcd at goshenarc.org Fri Apr 21 18:51:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 14:51:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 211849 SWOMCD SPC MCD 211848 FLZ000-GAZ000-212045- MESOSCALE DISCUSSION 0605 NWS STORM PREDICTION CENTER NORMAN OK 0148 PM CDT FRI APR 21 2006 AREAS AFFECTED...INTERIOR PORTIONS OF NORTHERN/CENTRAL FL AND FAR SOUTHERN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 211848Z - 212045Z THREAT FOR ISOLATED DAMAGING WIND GUSTS/HAIL AND PERHAPS A TORNADO WILL EXIST WITH THUNDERSTORM DEVELOPMENT THIS AFTERNOON ACROSS INTERIOR PORTIONS OF THE NORTHERN/CENTRAL FL PENINSULA INTO SOUTHERN GA. A WATCH IS NOT EXPECTED. WITH LITTLE OR NO BACKGROUND FORCING FOR ASCENT...SEABREEZE BOUNDARY INTERACTIONS ARE LEADING TO DEEPENING CU FIELD ACROSS INTERIOR PORTIONS OF NORTHERN/CENTRAL FL PENINSULA...WITH FIRST STORM DEVELOPMENT BETWEEN OCALA AND BROOKSVILLE FL. INCREASING THUNDERSTORM COVERAGE IS EXPECTED OVER THE NEXT FEW HOURS ACROSS INTERIOR FL INTO SOUTHERN GA...WITH STRONG/SEVERE STORMS POSSIBLE THROUGH EARLY EVENING. A WARM/MOIST BOUNDARY LAYER...COUPLED WITH SUFFICIENTLY COOL TEMPERATURES ALOFT...WILL LEAD TO MLCAPE OF 1500-2000 J/KG PER CURRENT TRENDS/ADJUSTED RUC SOUNDINGS. ALTHOUGH MODERATE INSTABILITY...PRIMARY LIMITING FACTOR FOR AN ORGANIZED SEVERE THREAT WILL BE RATHER WEAK VERTICAL SHEAR /15 KTS OR LESS 0-6 KM PER CURRENT WSR-88D VWPS AND REGIONAL 12Z RAOBS/. A PULSE-TYPE/EPISODIC SEVERE POTENTIAL WOULD BE THE NORM WITH THE SLOW MOVING STORMS...WITH THREATS FOR DAMAGING WET MICROBURSTS/HAIL AND PERHAPS A TORNADO VIA BOUNDARY INTERACTIONS. MARGINAL/ISOLATED NATURE OF THE OVERALL THREAT SUGGESTS A WATCH WILL NOT BE NEEDED. ..GUYER.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MLB...TBW...JAX...TAE... 30578310 30928259 30538175 28148098 27668186 28438241 29938298 WWWW From Mcd at goshenarc.org Fri Apr 21 20:43:01 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 16:43:01 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212040 SWOMCD SPC MCD 212039 GAZ000-ALZ000-FLZ000-212145- MESOSCALE DISCUSSION 0606 NWS STORM PREDICTION CENTER NORMAN OK 0339 PM CDT FRI APR 21 2006 AREAS AFFECTED...MS...GA...AL...WRN FL PNHDL CONCERNING...SEVERE THUNDERSTORM WATCH 232...233... VALID 212039Z - 212145Z REMAINING VALID PORTION OF WW 232 MAY BE ALLOWED TO EXPIRE AT 21Z. CONTINUE REMAINING VALID PORTION OF WW 233. PARTS OF SOUTHERN/ EASTERN AL INTO WESTERN GEORGIA ARE BEING MONITORED FOR POSSIBLE ADDITIONAL WW. WELL ORGANIZED CONVECTIVE SYSTEM HAS YET TO EVOLVE...BUT STILL APPEARS POSSIBLE LATE THIS AFTERNOON AS MID-LEVEL FORCING ASSOCIATED WITH A SOUTHERN BRANCH SHORT WAVE TROUGH LIFTS OUT OF LOUISIANA/ MISSISSIPPI TOWARD THE SOUTHERN APPALACHIANS. INFLUX OF DRIER LOWER /MID TROPOSPHERIC AIR AND DOWNWARD MIXING ACROSS PARTS OF SOUTHERN/ EASTERN ALABAMA HAS LOWERED BOUNDARY LAYER DEW POINTS SOME. HOWEVER...MIXED LAYER CAPE UP TO 1000 J/KG IS STILL SUPPORTIVE OF VIGOROUS UPDRAFTS IN FAVORABLE SHEAR ENVIRONMENT ASSOCIATED WITH 40 TO 50 KT CYCLONIC MID-LEVEL FLOW. MOST SIGNIFICANT THUNDERSTORM ACTIVITY WILL PROGRESS THROUGH BIRMINGHAM SHORTLY...AND LIKELY MONTGOMERY BY 22-23Z...POSSIBLY APPROACHING THE ATLANTA METROPOLITAN AREA WITH POTENTIAL FOR HAIL AND DAMAGING WINDS BY 22/00Z. ..KERR.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FFC...TAE...BMX...MOB... 31738815 32628837 33628714 34678430 33588378 32508417 31098546 30798673 30928818 WWWW From Mcd at goshenarc.org Fri Apr 21 21:00:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 17:00:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212058 SWOMCD SPC MCD 212057 CAZ000-212300- MESOSCALE DISCUSSION 0607 NWS STORM PREDICTION CENTER NORMAN OK 0357 PM CDT FRI APR 21 2006 AREAS AFFECTED...NORTHERN/CENTRAL CA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 212057Z - 212300Z THREAT FOR ISOLATED HAIL WILL INCREASE REMAINDER OF THE AFTERNOON ACROSS INTERIOR PORTIONS OF NORTHERN/CENTRAL CA. A WATCH IS NOT CURRENTLY ANTICIPATED...HOWEVER WILL CONTINUE TO MONITOR CONVECTIVE TRENDS. WATER VAPOR IMAGERY FEATURES UPPER LOW JUST OFF THE CENTRAL CA COAST. AS THIS LOW NEARS THE COAST...MID LEVEL LAPSE RATES WILL CONTINUE TO STEEPEN INTO INTERIOR CA. INITIAL THUNDERSTORM DEVELOPMENT IS ALREADY NOTED EAST OF THE BAY AREA...WITH INCREASING CONVECTIVE COVERAGE EXPECTED THROUGH LATE AFTERNOON FROM THE COASTAL AREAS INTO THE SACRAMENTO/SAN JOAQUIN VALLEYS. PROGRESSIVELY COOL TEMPERATURES ALOFT COUPLED WITH A MILD BOUNDARY LAYER AND UPPER 40S/LOWER 50S DEWPOINTS WILL LEAD TO POTENTIAL FOR MOST UNSTABLE CAPES IN EXCESS OF 1000 J/KG PER ADJUSTED RUC SOUNDINGS...ESPECIALLY IN AREAS FROM SACRAMENTO/STOCKTON AND SOUTH. PRIMARY SEVERE HAZARD IS LIKELY TO BE HAIL THROUGH EARLY EVENING...ALTHOUGH A FEW FUNNELS MAY BE POSSIBLE AS WELL. ..GUYER.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HNX...STO...MTR... 40482263 40562202 40142158 39442099 38172048 36791933 36461966 36372013 36902089 37822193 38772268 39342278 WWWW From Mcd at goshenarc.org Fri Apr 21 23:25:20 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 19:25:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 212323 SWOMCD SPC MCD 212322 SCZ000-NCZ000-GAZ000-TNZ000-220045- MESOSCALE DISCUSSION 0608 NWS STORM PREDICTION CENTER NORMAN OK 0622 PM CDT FRI APR 21 2006 AREAS AFFECTED...WRN SC...WRN NC...FAR ERN TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 212322Z - 220045Z THE THUNDERSTORMS DEVELOPING ACROSS THE WRN CAROLINAS AND NERN GA WILL LIKELY MAINTAIN A SEVERE THREAT OVER THE NEXT FEW HOURS. LARGE HAIL AND WIND DAMAGE SHOULD BE THE PRIMARY THREATS. SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS EXTENDING NWD ACROSS ERN GA INTO WRN NC WHERE DEWPOINTS ARE IN THE LOWER 60S F. LOW-LEVEL CONVERGENCE ALONG THE MOIST AXIS AND SFC HEATING IS RESULTING IN THUNDERSTORM DEVELOPMENT. STORMS SHOULD REMAIN RELATIVELY ISOLATED THIS EVENING DUE TO A LACK OF LARGE-SCALE ASCENT ACROSS THE REGION ASSOCIATED WITH AN UPPER-LEVEL RIDGE. HOWEVER...FORECAST SOUNDINGS SHOW MODERATE INSTABILITY REMAINING IN PLACE THIS EVENING WITH STEEP LAPSE RATES AND SUFFICIENT SHEAR FOR A SEVERE THREAT WITH LARGE HAIL AND ISOLATED WIND DAMAGE. DUE TO THE WEAK ASCENT...THE ACTIVITY SHOULD DECREASE IN INTENSITY AFTER SUNSET AS SFC TEMPS COOL AND INSTABILITY DECREASES ACROSS THE REGION. ..BROYLES.. 04/21/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RNK...CAE...GSP...MRX...FFC... 33148225 33348288 33808313 34578338 36178343 36218141 34908087 33358074 WWWW From Mcd at goshenarc.org Sat Apr 22 01:08:29 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 21:08:29 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220106 SWOMCD SPC MCD 220105 GAZ000-ALZ000-220300- MESOSCALE DISCUSSION 0609 NWS STORM PREDICTION CENTER NORMAN OK 0805 PM CDT FRI APR 21 2006 AREAS AFFECTED...SE AL...GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 220105Z - 220300Z THE SEVERE THREAT OVER SE AL AND GA WILL LIKELY INCREASE THIS EVENING AS AN MCS MOVES ENEWD TOWARD THE ATLANTA AREA. ADDITIONAL STORMS SHOULD INTENSIFY ACROSS SE AL AND SHOULD MOVE INTO SW GA LATER THIS EVENING. A WW WILL BECOME NECESSARY BY 0130Z. WATER VAPOR IMAGERY CURRENTLY SHOWS A SHORTWAVE TROUGH MOVING ENEWD ACROSS AL ATTM. THUNDERSTORMS ARE DEVELOPING ALONG THE LEADING EDGE OF ASCENT AND WILL LIKELY INCREASE IN COVERAGE AS THE TROUGH MOVES ACROSS THE REGION. ALTHOUGH WSR-88D VWPS CURRENTLY SHOW 0-6 KM SHEAR VALUES OF 30 TO 35 KT...THE MODERATE INSTABILITY SHOULD BE ENOUGH FOR STRONG MULTICELL STORMS OR PERHAPS ISOLATED SUPERCELLS. STEEP LOW-LEVEL LAPSE RATES SHOWN ON FORECASTS SOUNDINGS WILL FAVOR WIND DAMAGE WITH THE STRONGER CELLS. IN ADDITION...THE SHEAR PROFILES AND MODERATE INSTABILITY MAY ALLOW A FEW SUPERCELL STORMS TO DEVELOP CAPABLE OF LARGE HAIL AND ISOLATED WIND DAMAGE. ..BROYLES.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GSP...FFC...TAE...BMX...MOB... 31328422 31048503 31208593 31968640 32968604 33608527 34478414 34078292 33248274 WWWW From Mcd at goshenarc.org Sat Apr 22 03:42:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 21 Apr 2006 23:42:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220340 SWOMCD SPC MCD 220340 FLZ000-GAZ000-ALZ000-MSZ000-220545- MESOSCALE DISCUSSION 0610 NWS STORM PREDICTION CENTER NORMAN OK 1040 PM CDT FRI APR 21 2006 AREAS AFFECTED...FL PANHANDLE...SRN AL...SE MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 220340Z - 220545Z AN ISOLATED TORNADO THREAT WILL EXIST WITH ROTATING CELLS OVER THE NEXT FEW HOURS ACROSS SRN AL AND THE FL PANHANDLE. A TORNADO WATCH WILL BE ISSUED SHORTLY. A LINE OF STORMS IS CURRENTLY INTENSIFYING ALONG THE GULF COAST OF AL AND THE FL PANHANDLE. THE CONVECTION IS JUST AHEAD OF AN APPROACHING SHORTWAVE TROUGH OVER THE LOWER MS VALLEY AND SHOULD INCREASE IN COVERAGE OVER THE NEXT FEW HOURS. FORECAST SOUNDINGS FOR THIS AREA TONIGHT INCREASE VERTICAL SHEAR AS A MID-LEVEL JET APPROACHES THE REGION. IN ADDITION...MODERATE INSTABILITY IS PRESENT WITH STRONG LOW-LEVEL SHEAR AS INDICATED BY REGIONAL WSR-88D VWPS. THIS SHOULD BE ADEQUATE FOR ROTATING STORMS WITH A TORNADO POTENTIAL. ALSO...ISOLATED WIND DAMAGE AND HAIL WILL BE POSSIBLE WITH THE STRONGER STORMS. ..BROYLES.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB...LIX... 30028708 29978863 30268892 30718898 31248871 31408855 31508754 31368603 31158502 30468489 30078536 29978692 WWWW From Mcd at goshenarc.org Sat Apr 22 07:30:47 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 03:30:47 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220728 SWOMCD SPC MCD 220728 GAZ000-ALZ000-220830- MESOSCALE DISCUSSION 0611 NWS STORM PREDICTION CENTER NORMAN OK 0228 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS ERN AL...GA. CONCERNING...SEVERE THUNDERSTORM WATCH 235... VALID 220728Z - 220830Z WW WILL BE ALLOWED TO EXPIRE AS SCHEDULED AT 8Z. MRGL/ISOLATED SEVERE HAIL OR STRONG GUSTS CAPABLE OF MINOR DAMAGE MAY STILL OCCUR FROM MOST VIGOROUS CONVECTION IN COMPLEX MOVING EWD FROM SERN AL OVER SRN GA. HOWEVER ORGANIZED SEVERE RISK DOES NOT APPEAR GREAT ENOUGH TO WARRANT ADDITIONAL WW ATTM. HOWEVER...EXPECT INCREASE IN POTENTIAL FOR GEN TSTMS OVER SRN GA NEXT FEW HOURS...AS PORTIONS OF TSTM COMPLEX NOW OVER SERN AL AND FL PANHANDLE MOVE ENEWD. CYCLONIC TURNING IN REFLECTIVITY ANIMATIONS INDICATES EMBEDDED MCV MOVING ENEWD 30-35 KT OVER AREA BETWEEN AUO-DHN AS OF 715Z...WHICH MAY ENHANCE INSTABILITY ALOFT...IN COMBINATION WITH WEAK/AMBIENT/MIDLEVEL ASCENT AHEAD OF SHORTWAVE TROUGH...INDICATED IN MOISTURE CHANNEL IMAGERY INVOF MS/AL BORDER. THIS MAY RESULT IN MUCAPES UP TO AROUND 1200 J/KG. FOREGOING BOUNDARY LAYER SHOULD CONTINUE TO COOL DIABATICALLY...ROOTING STRONGEST BUOYANCY ABOVE SFC INVOF MOIST/SWLY LLJ. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAX...FFC...TAE...BMX... 31048581 31628608 32078604 32778491 32828364 32108278 31248317 31068414 WWWW From Mcd at goshenarc.org Sat Apr 22 07:56:42 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 03:56:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 220754 SWOMCD SPC MCD 220754 FLZ000-ALZ000-220930- MESOSCALE DISCUSSION 0612 NWS STORM PREDICTION CENTER NORMAN OK 0254 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS FL PANHANDLE...EXTREME SRN AL. CONCERNING...TORNADO WATCH 236... VALID 220754Z - 220930Z BUOYANCY AND VERTICAL SHEAR PROFILES SUITABLE FOR SUPERCELLS REMAIN ACROSS MOST OF WW AREA...HOWEVER ORIENTATION/STRUCTURE OF CONVECTION IS NOT PARTICULARLY FAVORABLE. CONTINUATION OF THIS TREND MAY COMPEL EARLY CANCELLATION OF SOME OR ALL THIS WW. WITH VPS RADAR DATA MISSING...WW IS NOT WELL SAMPLED FOR OBSERVATIONAL WINDS ALOFT. HOWEVER...MODIFIED RUC SOUNDINGS AND WIND TRENDS FROM SERN AL RADAR SUGGEST SLOWLY DIMINISHING VERTICAL SHEAR PROFILES...BUT WITH ENOUGH LOW LEVEL SPEED SHEAR REMAINING TO ENLARGE HODOGRAPHS...YIELDING 100-200 J/KG 0-1 KM SRH OVER PORTIONS WRN FL PANHANDLE. MLCAPES UP TOO 1500 J/KG ARE EVIDENT AS WELL...SUPPORTED BY UPPER 60S/LOW 70S F SFC DEW POINTS. BY CONTRAST...CONVECTIVE MODE HAS BECOME PROGRESSIVELY MORE DISORGANIZED AND LESS DISCRETE...WITH MAIN BAND OF ACTIVITY ORIENTED NEARLY PARALLEL TO DEEP-LAYER SHEAR AND MEAN FLOW VECTORS. WHEN ACCOUNTING FOR TRANSLATIONAL MCS MOTION...THIS APPEARS TO RESULT IN SLIGHTLY ANAFRONTAL REGIME ASSOCIATED WITH EFFECTIVE BOUNDARY...WHICH IS NOT CONDUCIVE TO REDEVELOPING DISCRETE MODE. ADDITIONAL DEVELOPMENT MAY MOVE INLAND FROM GULF OR OCCUR OVER ANTECEDENT WARM SECTOR...HOWEVER PROBABILITIES APPEAR LOW ATTM BECAUSE OF PRONOUNCED WEAKNESS IN SFC FLOW AND CONVERGENCE AHEAD OF MCS. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TAE...MOB... 29778867 30388776 30958657 30858517 30558479 29968452 29508508 29668569 29868687 29828789 WWWW From Mcd at goshenarc.org Sat Apr 22 10:38:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 06:38:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221036 SWOMCD SPC MCD 221035 NCZ000-VAZ000-221230- MESOSCALE DISCUSSION 0613 NWS STORM PREDICTION CENTER NORMAN OK 0535 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS CENTRAL/NRN NC...S-CENTRAL VA. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221035Z - 221230Z TSTM SQUALL LINE -- EXTENDING FROM NC/VA BORDER VICINITY MTV...THROUGH GSO AREA TO UNION COUNTY NC AS OF 1015Z -- SHOULD CONTINUE TO MOVE NEWD 35-45 KT TOWARD S-CENTRAL VA. OCCASIONAL GUSTS BELOW 50 KT SEVERE CRITERIA -- BUT CAPABLE OF DMG TO WEAK STRUCTURES AND TREES -- MAY CONTINUE ALONG WITH MARGINALLY SEVERE HAIL. ATTM...WW NOT EXPECTED. SFC MESOANALYSIS SHOWS DIFFUSE WARM FRONT FROM NERN WV SEWD ACROSS SERN VA...S OF WHICH SFC TEMPS SHOULD REMAIN LOW-MID 60S F FOR ANOTHER COUPLE HOURS BEFORE DIABATIC HEATING COMMENCES AND/OR CONVECTIVE BAND PASSES. MOISTURE CHANNEL IMAGERY INDICATES SOME LARGE SCALE ASCENT IS POSSIBLE FROM MID-UPPER LEVEL PERTURBATION THAT EVOLVED FROM MCV PRODUCED BY SE TX ACTIVITY 24 HOURS AGO. AHEAD OF THIS PERTURBATION...DEEP-LAYER WIND PROFILES SHOULD REMAIN NEARLY UNIDIRECTIONAL THROUGH BUOYANT LAYER...WITH ELEVATED MUCAPES AROUND 700-800 J/KG ROOTED JUST ABOVE SFC. OBSERVATION SITES OVER NRN SC AND WRN NC CROSSED BY THIS LINE HAVE MEASURED GUSTS IN 25-37 KT RANGE...LESS THAN TRANSLATIONAL SPEED OF SQUALL LINE ITSELF IN MOST AREAS. RELATIVELY STABLE LAYER NEAR SFC -- EVIDENT IN MODIFIED RUC SOUNDINGS -- SHOULD CONTINUE TO LIMIT STRENGTH AND AREAL EXTENT OF MOST INTENSE SFC WINDS WITH THIS ACTIVITY. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...RAH...RNK...GSP... 34908048 35578028 35887997 36327995 36578013 37457841 37287784 36607756 36457753 36017766 35177885 WWWW From Mcd at goshenarc.org Sat Apr 22 12:31:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 08:31:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221228 SWOMCD SPC MCD 221228 NCZ000-SCZ000-221400- MESOSCALE DISCUSSION 0614 NWS STORM PREDICTION CENTER NORMAN OK 0728 AM CDT SAT APR 22 2006 AREAS AFFECTED...PORTIONS CENTRAL/ERN SC...S-CENTRAL/SERN NC. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221228Z - 221400Z AREA IS BEING MONITORED FOR POSSIBLE WW. SHORT/INTENSIFYING LINE OF TSTMS...LOCATED BETWEEN AGS-CAE AS OF 12Z -- IS EXPECTED TO MOVE NEWD APPROXIMATELY 40 KT...CROSSING CAE AREA BY 13Z AND REACHING AREA BETWEEN FLO AND NC BORDER IN 14Z-15Z TIME FRAME GIVEN MOTION SIMILAR TO PRESENT. THIS BAND OF TSTMS MAY EXPAND -- BACKBUILDING EWD INTO MORE UNSTABLE AIR MASS -- AS IT MOVES NEWD ACROSS DISCUSSION AREA. MAIN THREAT WILL BE DAMAGING GUSTS...ESPECIALLY IN ANOTHER 2-3 HOURS AS ACTIVITY BECOMES MORE SFC-BASED. OCCASIONAL/MARGINALLY SEVERE HAIL ALSO IS POSSIBLE. EXPECT RELATIVELY FAST FORWARD SPEEDS TO CONTINUE IN ORDER FOR ACTIVITY TO MAINTAIN AT LEAST 10-15 KT STORM-RELATIVE INFLOW JUST ABOVE SFC...GIVEN 30-35 KT 850 MB WINDS EVIDENT IN REGIONAL VWP. FOREGOING SFC AIR MASS IS EXPECTED TO DESTABILIZE WITH ONSET OF DIABATIC SFC HEATING...WITH ONLY 2-3 DEG F WARMING NECESSARY TO ENSURE SFC-BASED LIFTED PARCEL BASED ON SHORT-TERM RUC FCST SOUNDINGS. MLCAPES MAY RISE TO 1000-1500 J/KG. WEAK SFC FLOW WILL CONTRIBUTE TO ENHANCED LOW LEVEL SHEAR VALUES THROUGH 0-3 KM LAYER...YIELDING SRH 100-200 J/KG. CAP APPARENT IN 12Z MHX SOUNDING WEAKENS WITH WWD EXTENT...AND WITH PROXIMITY TO INCREASING LARGE SCALE ASCENT ASSOCIATED WITH SHORTWAVE TROUGH LIFTING ENEWD ACROSS GA ATTM. THEREFORE ADDITIONAL DEVELOPMENT ALSO IS POSSIBLE SEPARATE FROM AFOREMENTIONED CONVECTIVE BAND...OVER ERN CAROLINAS. ..EDWARDS.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CHS...CAE...GSP... 33278146 34148173 35248041 35727930 35537865 34877799 33507909 33108034 WWWW From Mcd at goshenarc.org Sat Apr 22 16:23:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 12:23:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221620 SWOMCD SPC MCD 221620 FLZ000-221745- MESOSCALE DISCUSSION 0615 NWS STORM PREDICTION CENTER NORMAN OK 1120 AM CDT SAT APR 22 2006 AREAS AFFECTED...PARTS OF NRN FL/NRN FL PEN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221620Z - 221745Z SEVERE POTENTIAL SEEMS LIKELY TO INCREASE ACROSS PARTS OF NORTHEASTERN FLORIDA EARLY THIS AFTERNOON. WW IS NOT CURRENTLY ANTICIPATED...DUE PRIMARILY TO RELATIVELY SHORT TIME DURATION AND SOMEWHAT LIMITED AREAL COVERAGE/MAGNITUDE OF EXPECTED THREAT. SOUTHERN BRANCH SHORT WAVE TROUGH HAS CONTRIBUTED TO MAINTENANCE OF SMALL CONVECTIVE CLUSTER ACROSS AND EAST OF THE FLORIDA BIG BEND REGION. STRONGEST UPDRAFTS ARE ALREADY FAIRLY VIGOROUS...AND SEEM LIKELY TO INTENSIFY FURTHER NEXT FEW HOURS AS ELIMINATION OF NEAR SURFACE RADIATIONAL INVERSION ALLOWS DEVELOPMENT OUT OF BOUNDARY LAYER WITH CAPE OF 1500 TO 2000 J/KG. EMBEDDED WITHIN MODERATELY SHEARED ENVIRONMENT BENEATH 30 TO 40 KT CYCLONIC WESTERLY MID-LEVEL FLOW...DEVELOPING STORMS MAY POSE RISK OF MARGINALLY SEVERE HAIL AS THEY APPROACH GAINESVILLE BY 18Z. ASSOCIATED SURFACE COLD POOL SHOULD STRENGTHEN AS WELL...AND MAY BE ACCOMPANIED BY WINDS WHICH COULD BRIEFLY APPROACH SEVERE LIMITS ALONG GUST FRONT AS IT SPREADS EAST OF GAINESVILLE INTO COASTAL AREAS SOUTH OF JACKSONVILLE THROUGH DAYTONA BEACH BY 20Z. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MLB...TBW...JAX...TAE... 30248282 30348217 30158153 29688124 28928109 28918181 29208249 29438305 29858278 WWWW From Mcd at goshenarc.org Sat Apr 22 17:10:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 13:10:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221707 SWOMCD SPC MCD 221707 NCZ000-VAZ000-SCZ000-GAZ000-221830- MESOSCALE DISCUSSION 0616 NWS STORM PREDICTION CENTER NORMAN OK 1207 PM CDT SAT APR 22 2006 AREAS AFFECTED...CNTRL AND ERN NC...PARTS OF ERN SC AND SE VA CONCERNING...SEVERE THUNDERSTORM WATCH 237... VALID 221707Z - 221830Z CONTINUE WW 237. ADDITIONAL WW IS NOT CURRENTLY ANTICIPATED... BUT CONVECTIVE TRENDS NEAR AND TO THE LEE OF THE SOUTHERN APPALACHIANS...ACROSS PARTS OF NORTHEASTERN GEORGIA/SOUTH CAROLINA...ARE BEING MONITORED. MOST SIGNIFICANT IMPULSE EMBEDDED WITHIN BROADER SCALE SOUTHERN BRANCH TROUGH APPEARS TO BE JUST NOW SHIFTING EAST OF THE SOUTHERN APPALACHIANS. HOWEVER...SEVERAL WEAKER IMPULSES HAVE ALREADY PROGRESSED THROUGH CYCLONIC FLOW EXTENDING DOWNSTREAM...THROUGH THE SOUTHERN AND MID ATLANTIC COAST STATES. THIS INCLUDES ONE WAVE/WIND SHIFT WHICH HAS BECOME FOCUS FOR NARROW INTENSIFYING LINE OF CONVECTION FROM MYRTLE BEACH THROUGH RALEIGH INTO SOUTH CENTRAL VIRGINIA. WEAK TO MODERATE INSTABILITY AHEAD OF THIS ACTIVITY WILL SUPPORT A CONTINUING HAIL THREAT IN STRONGER STORMS. AND...30 TO 40 KT MEAN FLOW WILL CONTRIBUTE TO MODERATE NORTHEASTERLY STORM MOTIONS AND ENHANCED RISK OF STRONG GUSTY SURFACE WINDS ACROSS EASTERN NORTH CAROLINA/SOUTHEAST VIRGINIA THROUGH 21-22Z. SCATTERED THUNDERSTORMS ARE BEGINNING TO INCREASE IN NUMBER UPSTREAM...BUT LACK OF STRONGER LOW-LEVEL FOCUS AND DESTABILIZATION IN WAKE OF DOWNSTREAM CONVECTION SEEMS LIKELY TO LIMIT SEVERE POTENTIAL. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CHS...CAE...GSP...JAX...FFC...TAE... 32787933 32438061 31968164 31528347 32178394 34008375 35198271 35458051 36597861 36847816 37427728 37437691 36117605 35467602 34257669 33417774 33227820 33137844 WWWW From Mcd at goshenarc.org Sat Apr 22 19:22:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 15:22:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221919 SWOMCD SPC MCD 221919 MIZ000-OHZ000-INZ000-222115- MESOSCALE DISCUSSION 0617 NWS STORM PREDICTION CENTER NORMAN OK 0219 PM CDT SAT APR 22 2006 AREAS AFFECTED...LWR MI...NW OH...NRN AND CNTRL IND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221919Z - 222115Z A WW IS NOT ANTICIPATED IN THE NEAR TERM...BUT COULD BECOME NECESSARY LATER THIS AFTERNOON. TRENDS ARE BEING MONITORED. AREA OF STRONGER MID-LEVEL FORCING/COOLING IS CURRENTLY OVERSPREADING LOWER MICHIGAN ASSOCIATED WITH IMPULSE PIVOTING AROUND SOUTHEASTERN QUADRANT OF CLOSED UPPER LOW. THIS IS CONTRIBUTING TO WEAK DESTABILIZATION...AND ONGOING DEEPENING CONVECTIVE DEVELOPMENT TO THE NORTHEAST/EAST OF MUSKEGON. MIXED LAYER CAPE IS STILL ONLY ON THE ORDER OF 500 J/KG...BUT WITH FURTHER HEATING IN MODERATELY SHEARED ENVIRONMENT...POTENTIAL FOR HAIL APPROACHING OR BRIEFLY EXCEEDING SEVERE LIMITS SHOULD INCREASE. MOST VIGOROUS THUNDERSTORM ACTIVITY APPEARS LIKELY TO DEVELOP SOUTHEASTWARD TOWARD THE DETROIT AREA THROUGH 21-22Z. THEREAFTER...MODELS SEEM TO SUGGEST STRONGER MID-LEVEL FORCING WILL BECOME REORIENTED FROM SOUTHERN MICHIGAN SOUTHWESTWARD THROUGH PARTS OF NORTHERN/CENTRAL INDIANA...AS A 70 KT 500 MB JET STREAK NOSES AROUND SOUTHWESTERN PERIPHERY OF CLOSED LOW. PRE-FRONTAL THERMAL RIDGE AXIS ACROSS THIS REGION WILL BECOME FOCUS FOR STRONGEST DESTABILIZATION...IN KINEMATIC ENVIRONMENT SUPPORTIVE OF UPDRAFT ROTATION. ISOLATED LOW TOPPED SUPERCELLS APPEARS POSSIBLE...WITH LARGE HAIL/DAMAGING WIND GUSTS PRIMARY THREATS. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CLE...ILN...DTX...APX...IWX...GRR...IND... 43788588 44388579 44628499 44198345 43148267 42108261 40618382 39228594 39538720 40338716 41648574 WWWW From Mcd at goshenarc.org Sat Apr 22 19:55:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 15:55:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 221953 SWOMCD SPC MCD 221952 TXZ000-NMZ000-222145- MESOSCALE DISCUSSION 0618 NWS STORM PREDICTION CENTER NORMAN OK 0252 PM CDT SAT APR 22 2006 AREAS AFFECTED...EASTERN NM INTO WEST/SOUTHWEST TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 221952Z - 222145Z LARGE HAIL/DAMAGING WIND POTENTIAL IS EXPECTED TO INCREASE REMAINDER OF THE AFTERNOON/EARLY EVENING ACROSS EASTERN NM INTO WEST TX. MONITORING FOR A POSSIBLE SEVERE THUNDERSTORM WATCH...POSSIBLY BY 21Z-22Z. VISIBLE SATELLITE IMAGERY FEATURES TOWERING CU DEVELOPING IN VICINITY NM/SOUTHWEST TX MOUNTAINS AT MID AFTERNOON...NAMELY NEAR ROSWELL/ARTESIA NM. EVEN IN PRESENCE OF AFTERNOON BOUNDARY LAYER MIXING...50S/LOWER 60S F SURFACE DEWPOINTS HAVE BEEN MAINTAINED ACROSS WEST TX INTO FAR SOUTHEAST NM WITHIN LOW LEVEL SOUTHEASTERLY UPSLOPE FLOW. CONVECTIVE INHIBITION WILL CONTINUE TO ERODE OVER THE NEXT SEVERAL HOURS ACROSS THE EASTERN NM/WEST TX PLAINS...WITH INCREASING THUNDERSTORM COVERAGE/SEVERE POTENTIAL SPREADING EASTWARD EARLY THIS EVENING. LATEST RUC SOUNDINGS SUGGEST POTENTIAL FOR 1500-2000 J/KG MLCAPE. TRENDS FROM THE TUCUMCARI/WHITE SANDS NM PROFILERS SUGGEST A DEEPENING/LOWERING OF RELATIVELY STRONGER MID LEVEL FLOW OVER THE PAST SEVERAL HOURS...WITH 35-40 KTS SOUTHWESTERLY WINDS COMMON IN THE MID LEVELS. COUPLED WITH THE DEGREE OF INSTABILITY/LOW LEVEL SOUTHEASTERLY TRAJECTORIES...IT APPEARS THAT SUFFICIENT VERTICAL SHEAR WILL BE SUPERIMPOSED ACROSS THE AMBIENT WARM SECTOR FOR SUPERCELLS AND/OR WELL ORGANIZED MULTICELL CLUSTERS. ACTIVITY IS LIKELY TO DEVELOP/EVOLVE INTO WEST/NORTHWEST TX THIS EVENING WITH A CONTINUED LARGE HAIL THREAT...WITH DAMAGING WIND POTENTIAL POSSIBLY INCREASING AS STORMS GROW UPSCALE. IT APPEARS A SEVERE TSTM WATCH MAY BE NEEDED BY THE 21Z-22Z TIMEFRAME. ..GUYER.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...AMA...MAF...ABQ...EPZ... 31520490 32570493 34550442 35810361 35850175 34910117 32710205 31000258 30970385 WWWW From Mcd at goshenarc.org Sat Apr 22 20:21:38 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 16:21:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222019 SWOMCD SPC MCD 222018 MOZ000-222215- MESOSCALE DISCUSSION 0619 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT SAT APR 22 2006 AREAS AFFECTED...MO OZARKS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 222018Z - 222215Z VIGOROUS CONVECTIVE DEVELOPMENT IS POSSIBLE BEFORE DARK. HOWEVER...IT SEEMS LIKELY THAT ANY SEVERE THREAT WILL BE FAIRLY LOCALIZED...AND A WW IS NOT CURRENTLY ANTICIPATED. AHEAD OF DEVELOPING COLD FRONT...ASSOCIATED WITH IMPULSE ROTATING AROUND SOUTHWESTERN PERIPHERY OF UPPER MISSISSIPPI VALLEY CLOSED LOW...LOW/MID-LEVEL WARM ADVECTION IS BECOMING MAXIMIZED NEAR THE MISSOURI OZARKS. THIS IS OCCURRING ON EASTERN FRINGE OF CAPPING LOW/MID-LEVEL PLAINS THERMAL RIDGE...WHERE MID-LEVEL LAPSE RATES ARE STEEP...AND CONTRIBUTING TO POTENTIAL INSTABILITY. LATEST OBJECTIVE ANALYSIS SUGGEST MIXED LAYER CAPE MAY INCREASE INTO THE 500 TO 1000 J/KG RANGE BY LATE AFTERNOON. MID-LEVEL SUBSIDENCE HAS SUPPRESSED CONVECTIVE DEVELOPMENT TO THIS POINT...BUT MODELS SUGGEST THIS WILL WEAKEN/SHIFT OFF TO THE EAST LATER THIS AFTERNOON AND EVENING. DEEPENING BOUNDARY LAYER BASED CUMULUS FIELD IS ALREADY EVIDENT ALONG THE MISSOURI/KANSAS BORDER TO THE NORTHEAST OF CHANUTE. IT APPEARS POSSIBLE THIS THAT ACTIVITY COULD CONTINUE TO DEVELOP INTO ISOLATED THUNDERSTORM ACTIVITY BEFORE 23/00Z. FRONTAL FORCING WILL ENHANCE LIFT FROM SOUTH CENTRAL MISSOURI THROUGH NORTH CENTRAL KANSAS...BUT CAP SEEMS LIKELY TO HOLD TO THE WEST OF THE MISSOURI/KANSAS BORDER. IF STORMS DEVELOP...SHEAR BENEATH 50+ KT NORTHWESTERLY MID-LEVEL FLOW WILL BE SUFFICIENT FOR SUPERCELLS...WITH ENHANCED RISK OF LARGE HAIL/DAMAGING WIND GUSTS. ..KERR.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX... 38419443 38679357 38559250 38469162 37899122 37399193 37369340 37799444 WWWW From Mcd at goshenarc.org Sat Apr 22 22:01:17 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 18:01:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222158 SWOMCD SPC MCD 222158 NCZ000-SCZ000-GAZ000-230000- MESOSCALE DISCUSSION 0620 NWS STORM PREDICTION CENTER NORMAN OK 0458 PM CDT SAT APR 22 2006 AREAS AFFECTED...SERN VA...ERN NC/SC....ERN GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 222158Z - 230000Z ...NO ADDITIONAL WATCHES ARE CURRENTLY PLANNED FOR THE AREA... SEVERAL LINES/CLUSTERS OF STRONG STORMS SHOULD CONTINUE TO POSE A MARGINAL HAIL/WIND THREAT ACROSS PORTIONS OF EXTREME SERN VA...ERN NC AND SC...AND ERN GA FOR A COUPLE MORE HOURS. HOWEVER...LATEST DIAGNOSTIC DATA SUGGESTS MOIST/MARGINAL LAPSE RATES ACROSS THE REGION AFTER SEVERAL HOURS OF DEEP CONVECTION. WHILE A FEW POCKETS OF STRONGER INSTABILITY AND MODEST DEEP-LAYER FLOW PERSIST... DIMINISHING DIURNAL AND LARGE SCALE FORCING SHOULD RESULT IN A GRADUAL DECLINE IN STORM ORGANIZATION/INTENSITY. A FEW WEAKLY ORGANIZED MULTICELLULAR CLUSTERS REMAIN ONGOING WITH ATTENDANT THREAT OF SMALL HAIL...AND PERHAPS ONE OR TWO STRONG TO DAMAGING WIND GUSTS...BUT A NEW SEVERE TSTM WATCH DOES NOT APPEAR LIKELY AT THIS TIME. ..CARBIN.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MHX...RAH...ILM...CHS...CAE...JAX...FFC... 32128084 31558289 33638080 34628004 35957914 36157822 36017727 35697697 34927671 33897796 33467905 32518033 WWWW From Mcd at goshenarc.org Sat Apr 22 23:26:02 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 19:26:02 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 222323 SWOMCD SPC MCD 222323 TXZ000-NMZ000-230130- MESOSCALE DISCUSSION 0621 NWS STORM PREDICTION CENTER NORMAN OK 0623 PM CDT SAT APR 22 2006 AREAS AFFECTED...EASTERN NM/WEST TX CONCERNING...SEVERE THUNDERSTORM WATCH 238... VALID 222323Z - 230130Z SEVERE THUNDERSTORM WATCH 238 CONTINUES UNTIL 03Z ACROSS FAR SOUTHEAST NM/SOUTHWEST TX. MONITORING FOR AN ADDITIONAL WATCH ISSUANCE TO THE NORTH/NORTHEAST OF WW 238 INTO WEST/NORTHWEST TX. AS OF 2315Z...SCATTERED STRONG STORMS ARE ONGOING ACROSS EAST CENTRAL/SOUTHEAST NM -- NAMELY ALONG HIGHWAY 285 CORRIDOR FROM SOUTHWEST OF TUCUMCARI TO NEAR ROSWELL/LOVINGTON -- INTO THE PECOS VALLEY/BIG BEND AREA OF SOUTHWEST TX. STORMS ARE LIKELY TO CONTINUE TO DEVELOP NORTHEASTWARD INTO FAR WEST/NORTHWEST TX THROUGH MID EVENING. LOW LEVEL MOISTURE INFLUX VIA SOUTHEASTERLY LOW LEVEL WINDS IS TENDING TO OFFSET VERTICAL MIXING...WITH PERSISTENCE OF LOWER/MIDDLE 50S F DEWPOINTS AS FAR NORTH AS THE LUBBOCK AREA PER THE WEST TX MESONET. LATEST TUCUMCARI PROFILER DATA SUPPORTS EFFECTIVE SHEAR OF 35-40 KTS...FAVORABLE FOR WELL ORGANIZED CLUSTERS/EMBEDDED SUPERCELLS. WHILE LARGE HAIL WILL LIKELY BE THE PRIMARY HAZARD...ONE OR MORE MCS CLUSTERS MAY EVOLVE INTO FAR WEST/NORTHWEST TX...WITH COLD POOL GENERATION/INCREASING SOUTHERLY LOW LEVEL JET POSSIBLY SUPPORTING SOME DAMAGING WIND THREAT AS WELL. ..GUYER.. 04/22/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...AMA...MAF...ABQ... 33780452 35370380 35580247 34880162 33490139 30940263 30580415 32180452 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 03:06:57 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 22 Apr 2006 23:06:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230304 SWOMCD SPC MCD 230244 MOZ000-KSZ000-230445- MESOSCALE DISCUSSION 0622 NWS STORM PREDICTION CENTER NORMAN OK 0944 PM CDT SAT APR 22 2006 AREAS AFFECTED...NERN KS....WRN/CNTRL MO... CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230244Z - 230445Z THUNDERSTORMS ARE EXPECTED TO BECOME MORE NUMEROUS OVERNIGHT FROM NERN KS ACROSS WRN...CNTRL...AND ERN MO. A FEW OF THE STRONGER CELLS WILL LIKELY PRODUCE HAIL. STRENGTHENING ISENTROPIC ASCENT AND MOISTURE FLUX ACROSS NEARLY STATIONARY FRONTAL ZONE SITUATED FROM ECNTRL KS TO SCNTRL MO WERE LIKELY AIDING STORM INITIATION FROM TOP/MKC AREA TO SERN MO LATE THIS EVENING. PLUME OF STEEP MID LEVEL LAPSE RATES...COUPLED WITH STRONG THETA-E ADVECTION AROUND 850 MB...WERE CONTRIBUTING TO MUCAPE AROUND 1000 J/KG FOR UPDRAFTS ROOTED BETWEEN 850MB AND 700MB. GIVEN NOCTURNAL INCREASE IN LOW LEVEL MASS INFLOW ACROSS THE FRONTAL BAND...WOULD EXPECT CONVECTION TO CONTINUE TO DEVELOP ALONG THE EDGE OF THE PLAINS CAPPING INVERSION FOR THE NEXT FEW HOURS. VERY STRONG EFFECTIVE SHEAR OF 50-70KT WILL PROMOTE STORM ROTATION WITH A FEW STORMS POSSIBLY EXHIBITING SUPERCELL CHARACTERISTICS. PRIMARY THREAT FROM THIS ACTIVITY WILL REMAIN HAIL. GREATER SEVERE STORM COVERAGE MAY BE INHIBITED BY LACK OF MORE WELL-DEFINED LARGE SCALE INFLUENCE ON ASCENT AS WELL AS SOMEWHAT LIMITED EXTENT OF MOIST AXIS FEEDING INTO THE ZONE OF STRONG FORCING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LSX...SGF...EAX...TOP...ICT... 37929497 38249656 39279768 39629727 39629524 39379418 39069313 38349063 38099037 37889046 37649072 37589117 37609140 37629180 37629251 37789364 37819438 WWWW From Mcd at goshenarc.org Sun Apr 23 07:15:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 03:15:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 230712 SWOMCD SPC MCD 230712 TXZ000-NMZ000-230945- MESOSCALE DISCUSSION 0625 NWS STORM PREDICTION CENTER NORMAN OK 0212 AM CDT SUN APR 23 2006 AREAS AFFECTED...PORTIONS W TX AND EXTREME SERN NM. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 230712Z - 230945Z TSTMS ARE FORMING OVER PORTIONS PECOS VALLEY/PERMIAN BASIN REGIONS...FROM ERN CULBERSON COUNTY TX ENEWD ACROSS SERN CORNER OF NM. THIS ACTIVITY MAY INCREASE IN COVERAGE/INTENSITY AS IT MOVES ENEWD 15-20 KT ACROSS DISCUSSION AREA. OCCASIONAL HAIL IS POSSIBLE...HOWEVER SEVERE THREAT DOES NOT APPEAR SUFFICIENTLY ORGANIZED ATTM TO WARRANT WW. CONVENTIONAL SFC DATA AND W TX MESONET OBS INDICATE OUTFLOW BOUNDARY FROM EARLIER ACTIVITY EXTENDS FROM KENT COUNTY SWWD ACROSS MARTIN COUNTY TX...TO NEAR SERN TIP OF NM...BEFORE BECOMING DIFFUSE. AIR MASS ON BOTH SIDES OF BOUNDARY SHOULD CONTINUE GRADUAL DIABATIC COOLING...BENEATH 40-50 KT SSELY LLJ NOW EVIDENT IN MAF VWP AND JTN PROFILER. SUFFICIENT MOISTURE IS EVIDENT UPSTREAM TO SUPPORT CURRENT AND ADDITIONAL CONVECTIVE DEVELOPMENT OVER THIS REGION...BASED ON 00Z DRT RAOB AND 850 MB ANALYSIS. ACTIVITY SHOULD REMAIN ROOTED ABOVE SFC...WITH 8-9 DEG C/KM MIDLEVEL LAPSE RATES SUPPORTING ELEVATED MUCAPES AROUND 1000 J/KG ABOVE WRN PORTION OF OUTFLOW AIR MASS. CONVECTION SHOULD CONTINUE TO BECOME MORE DISORGANIZED WITH EWD EXTENT ACROSS SOUTH PLAINS/PERMIAN BASIN REGION. WEAK MIDLEVEL FLOW IN 500-700 MB LAYER WILL BE A LIMITING FACTOR FOR DEEP-LAYER SHEAR...RESULTING IN EFFECTIVE SHEARS IN 20-35 KT RANGE. ALSO...MODIFIED RUC SOUNDINGS SUGGEST INCREASING CINH FROM MAF/LBB LONGITUDE EWD. ..EDWARDS.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...MAF... 31300378 31500407 31920405 32230386 32650305 33000220 32790134 32330129 31430229 31120332 31150370 WWWW From Mcd at goshenarc.org Sun Apr 23 20:17:46 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 16:17:46 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232015 SWOMCD SPC MCD 232014 KSZ000-OKZ000-TXZ000-232215- MESOSCALE DISCUSSION 0626 NWS STORM PREDICTION CENTER NORMAN OK 0314 PM CDT SUN APR 23 2006 AREAS AFFECTED...WRN KS TO ERN TX PANHANDLE CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232014Z - 232215Z ...SEVERE THUNDERSTORM WATCH WILL BE REQUIRED FOR PORTIONS OF THE HIGH PLAINS OF KS...OK/TX PANHANDLE... BOUNDARY LAYER HAS WARMED RAPIDLY ACROSS THE CNTRL/SRN HIGH PLAINS...ESPECIALLY POST DRYLINE WHERE LOWEST 3KM LAPSE RATES ARE NEAR DRY ADIABATIC. IT APPEARS DRYLINE HAS MIXED AS FAR EAST AS IT WILL GO THIS AFTERNOON...WITH AN APPARENT NWWD MOISTURE SURGE NOW ADVECTING INTO THE ERN TX PANHANDLE AS PRESSURE FALLS FOCUS IN THE LEE OF THE SRN CO ROCKIES. STEEP LAPSE RATE ENVIRONMENT HAS AIDED HIGH BASED CONVECTION WITH ISOLATED LIGHTNING OVER SERN CO/SWRN KS...WHICH IS SPREADING NEWD AT ROUGHLY 40KT. THIS SPEED WOULD ALLOW DEEP CONVECTION/BOUNDARY LAYER MOISTURE INTERSECTION BY 21Z. ADDITIONALLY...BOUNDARY LAYER CU IS DEVELOPING RAPIDLY ALONG DRYLINE ACROSS THE TX PANHANDLE. IT APPEARS SIGNIFICANT THUNDERSTORM DEVELOPMENT WILL OCCUR ACROSS THIS REGION OVER THE NEXT FEW HOURS AND SEVERE THUNDERSTORM WATCH WILL BE ISSUED SOON. ..DARROW.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...GID...DDC...GLD...AMA... 34830182 36570138 37800086 39520128 39419944 35450020 WWWW From Mcd at goshenarc.org Sun Apr 23 22:15:04 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 18:15:04 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232212 SWOMCD SPC MCD 232212 MOZ000-KSZ000-232345- MESOSCALE DISCUSSION 0627 NWS STORM PREDICTION CENTER NORMAN OK 0512 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...SWRN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232212Z - 232345Z ERN KS AND SWRN MO CONTINUE TO BE MONITORED FOR POTENTIALLY RAPID SEVERE TSTM DEVELOPMENT THIS EVENING. WARM FRONT...REINFORCED BY CONVECTIVE OUTFLOW ACROSS SWRN MO...APPEARS IN LATEST MESOANALYSIS NORTH OF A SLN-EMP-JLN LINE. PERSISTENT MESOSCALE FORCING NEAR THE BOUNDARY...COUPLED WITH STRONG HEATING AND MOISTENING ACROSS THE WARM SECTOR...ARE EXPECTED TO RESULT IN TSTM INITIATION THIS EVENING. LARGE SCALE LIFT BENEATH UPPER RIDGE...WHILE NOT CURRENTLY SIGNIFICANT...MAY BE ENHANCED BY APPROACH OF MID/UPPER LEVEL DISTURBANCE CRESTING THE RIDGE AXIS ACROSS NWRN KS ATTM. NOCTURNAL INCREASE IN LOW LEVEL JET ACROSS THE FRONT WILL ALSO INCREASE TSTM DEVELOPMENT POTENTIAL. AIR MASS BEING TRANSPORTED INTO THE ZONE OF FORCING IS VERY UNSTABLE AND SHOULD FUEL INTENSE UPDRAFTS. LATEST MODEL GUIDANCE APPEARS TO SUPPORT STORM DEVELOPMENT ACROSS THE AREA IN THE 00Z-03Z TIME FRAME WITH THE STRONGEST VERTICAL MOTION OCCURRING NORTH OF THE SURFACE BOUNDARY. GENERALLY WEAK LOW LEVEL FLOW TOPPED BY MODEST WLY FLOW OF 40-50KT IN THE MID LEVELS WILL RESULT IN SUFFICIENT SHEAR FOR STORM ROTATION. SHEAR NEAR THE BOUNDARY WILL LIKELY STRENGTHEN THIS EVENING AS LOW LEVEL FLOW INCREASES AND STORM INTERACTIONS LOCALLY REINFORCE HORIZONTAL THERMAL GRADIENTS. SEVERE HAIL AND WIND APPEAR POSSIBLE AND A TORNADO OR TWO CANNOT BE RULED FROM ANY CELL TRACKING NEAR THE FRONT THIS EVENING. ..CARBIN.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT... 38149294 36919331 37339741 38869763 39519684 39149403 38799317 WWWW From Mcd at goshenarc.org Sun Apr 23 23:49:50 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 19:49:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 232347 SWOMCD SPC MCD 232346 TXZ000-240115- MESOSCALE DISCUSSION 0628 NWS STORM PREDICTION CENTER NORMAN OK 0646 PM CDT SUN APR 23 2006 AREAS AFFECTED...TX SOUTH PLAINS/CAPROCK VICINITY CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 232346Z - 240115Z ALTHOUGH CONVECTIVE INITIATION REMAINS UNCERTAIN...A CONDITIONAL THREAT FOR LARGE HAIL/DAMAGING WINDS EXISTS GIVEN THUNDERSTORM DEVELOPMENT EARLY THIS EVENING ACROSS THE TX SOUTH PLAINS/CAPROCK VICINITY. A WATCH IS NOT CURRENTLY ANTICIPATED. VISIBLE SATELLITE OVER THE PAST FEW HOURS PORTRAYS MODEST CU FIELD/FAILED ATTEMPTS AT CONVECTIVE INITIATION NEAR THE LUBBOCK VICINITY LATE THIS AFTERNOON. WHILE MASS FIELDS ARE BETTER FOCUSED TO THE NORTH/EAST OF THE REGION...SUFFICIENT HEATING/MIXING IN VICINITY OF THE DRYLINE HAS LARGELY ERODED THE CONVECTIVE INHIBITION ACROSS THE TX SOUTH PLAINS/CAPROCK VICINITY PER ADJUSTED RUC SOUNDINGS/18Z REESE RAOB. IN PRESENCE OF MODEST MASS CONVERGENCE...SOME WINDOW FOR THUNDERSTORM DEVELOPMENT YET REMAINS OVER THE NEXT FEW HOURS ACROSS WEST TX. GIVEN INITIATION...COMBINATION OF MODERATE INSTABILITY/MODEST VERTICAL SHEAR OF 25-30 KTS WOULD SUPPORT AT LEAST A SHORT-LIVED SEVERE THREAT...WITH LARGE HAIL/DAMAGING WIND POTENTIAL. EVEN PROVIDED CONVECTIVE INITIATION...CURRENT EXPECTATIONS ARE THAT DEVELOPMENT WOULD REMAIN SUFFICIENTLY ISOLATED TO PRECLUDE A WATCH ISSUANCE. ..GUYER.. 04/23/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LUB...MAF... 34260284 34560161 34280043 32610079 32850264 WWWW From Mcd at goshenarc.org Mon Apr 24 00:12:48 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 20:12:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240010 SWOMCD SPC MCD 240009 KSZ000-COZ000-240145- MESOSCALE DISCUSSION 0629 NWS STORM PREDICTION CENTER NORMAN OK 0709 PM CDT SUN APR 23 2006 AREAS AFFECTED...NERN CO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240009Z - 240145Z TSTMS WITH HAIL MAY INCREASE FROM THE FRONT RANGE ENEWD ACROSS NERN CO THIS EVENING. STRONG FRONTAL SURGE AND DEEPENING UPSLOPE FLOW WILL COMBINE WITH POST FRONTAL MOISTURE AND INSTABILITY TO FUEL A FEW STRONG TO SEVERE STORMS ACROSS THE REGION TONIGHT. INITIATION ON THE FRONT RANGE HAS BEGUN WITH HAIL RECENTLY REPORTED IN THE DENVER AREA. GIVEN STRENGTHENING LARGE SCALE ASCENT ASSOCIATED WITH THE APPROACH OF FOUR CORNERS SHORT WAVE TROUGH...AND PRESENCE OF DEVELOPING LEE-SIDE CYCLONE AND SURFACE FRONT EXTENDING EWD INTO NWRN KS...FEATURES APPEAR IN PLACE TO SUPPORT ADDITIONAL TSTM DEVELOPMENT ACROSS THE REGION. STRONG DIRECTIONAL AND SPEED SHEAR WITHIN THE CLOUD-BEARING LAYER WILL FURTHER PROMOTE STORM INTENSITY WITH HAIL APPEARING TO BE THE PRIMARY THREAT. AREA WILL CONTINUE TO BE MONITORED FOR INCREASING STORM COVERAGE BUT A WATCH DOES NOT APPEAR IMMINENT. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GLD...PUB...BOU... 39050316 38890428 38940503 39200523 39600527 40180497 40560425 40750370 40810322 40740290 40640268 40510233 40210214 39920209 39640204 39320203 WWWW From Mcd at goshenarc.org Mon Apr 24 01:01:24 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 21:01:24 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240058 SWOMCD SPC MCD 240058 MOZ000-KSZ000-240230- MESOSCALE DISCUSSION 0630 NWS STORM PREDICTION CENTER NORMAN OK 0758 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...WRN MO CONCERNING...SEVERE THUNDERSTORM WATCH 240... VALID 240058Z - 240230Z ISOLATED CELLS HAVE RECENTLY DEVELOPED ALONG QUASI-STATIONARY BOUNDARY FROM NERN KS INTO WRN MO. BASED ON LATEST SOUNDING INFORMATION FROM SGF AND TOP...MODIFIED FOR ESTIMATED ENVIRONMENTAL CONDITIONS NEAR THE FRONT...ISOLATED TORNADO POTENTIAL MAY BE INCREASING. RECENT DISCRETE STORM DEVELOPMENT ON THE FRONT IN OTTAWA AND MORRIS COUNTIES HAS OCCURRED ON THE SYNOPTIC FRONT WHERE SOUNDING AND PROFILER DATA SUGGEST STORM RELATIVE HELICITY (SRH) MAY BE QUITE HIGH. BASED ON PROXIMITY RAOB AND PROFILER DATA...0-1KM SRH WAS CURRENTLY ESTIMATED AT OVER 150 M2/S2...WHILE 0-3KM SRH MAY BE AS HIGH AS 400 M2/S2 FOR 300/12KT CELL MOTION. IN ADDITION TO RELATIVELY LOW LFC OF AROUND 1-2KM NEAR THE BOUNDARY THIS WOULD SUPPORT THE POTENTIAL FOR STRONG LOW LEVEL STORM ROTATION AND PERHAPS TORNADO FORMATION FOR UPDRAFTS REMAINING NEAR THE FRONTAL ZONE OVER THE NEXT HOUR OR SO. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 02:28:58 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 22:28:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240226 SWOMCD SPC MCD 240226 MOZ000-KSZ000-240330- MESOSCALE DISCUSSION 0631 NWS STORM PREDICTION CENTER NORMAN OK 0926 PM CDT SUN APR 23 2006 AREAS AFFECTED...TX/OK PNHDLS...NWRN OK...WRN KS CONCERNING...SEVERE THUNDERSTORM WATCH 239... VALID 240226Z - 240330Z TSTM COVERAGE AND INTENSITY WAS DECREASING ACROSS SEVERE TSTM WATCH 239 AT THIS HOUR. DRY LINE WAS RETREATING NWWD ACROSS THE WRN PORTIONS OF THE PNHDLS AS LEE-SIDE LOW GRADUALLY STRENGTHENS OVER SERN CO. LATEST RUC AND SREF GUIDANCE INDICATED THE THREAT FOR ORGANIZED SEVERE STORMS WITHIN WATCH 239 REGION SHOULD REMAIN LOW FOR THE REMAINDER OF THE NIGHT AND NO ADDITIONAL WATCHES ARE ANTICIPATED IN THIS AREA. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 02:50:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 22:50:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240247 SWOMCD SPC MCD 240247 MOZ000-KSZ000-240415- MESOSCALE DISCUSSION 0632 NWS STORM PREDICTION CENTER NORMAN OK 0947 PM CDT SUN APR 23 2006 AREAS AFFECTED...ERN KS...WRN MO CONCERNING...SEVERE THUNDERSTORM WATCH 240... VALID 240247Z - 240415Z ...LARGE AND POTENTIALLY DANGEROUS MCS HAS EVOLVED ACROSS SERN KS... EXPECT LINEAR MCS WITH MESOCYCLONIC COMMA-HEAD COMPLEX TO CONTINUE MOVING EAST AT UP TO 50KT ACROSS SERN KS OVER THE NEXT COUPLE OF HOURS. STRONG TO DAMAGING WIND GUSTS AND VERY LARGE HAIL SHOULD ACCOMPANY THIS SYSTEM ACROSS LYON...COFFEY...GREENWOOD...AND WOODSON COUNTIES OVER THE NEXT HOUR AND A HALF. ACTIVITY MAY THEN MERGE WITH OTHER INTENSE STORMS FORMING NEAR STATIONARY WARM FRONT FROM ALLEN AND ANDERSON COUNTIES IN EXTREME SERN KS...TO VERNON...ST. CLAIR...CEDAR...AND HICKORY COUNTIES IN WRN MO. ANOTHER INTENSE RIGHT-MOVING SUPERCELL STORM WAS CROSSING THE LAWRENCE KS AREA. IN ADDITION TO TORNADO POTENTIAL AND DAMAGING WINDS FROM THIS CELL... VERY LARGE AND DAMAGING HAIL WILL ALSO BE POSSIBLE. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...EAX...TOP...ICT...GID... 37759380 38229621 38669810 39219836 39319755 38939604 38479444 38359385 38249336 37799314 WWWW From Mcd at goshenarc.org Mon Apr 24 03:15:49 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sun, 23 Apr 2006 23:15:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240310 SWOMCD SPC MCD 240310 KSZ000-NEZ000-COZ000-240445- MESOSCALE DISCUSSION 0633 NWS STORM PREDICTION CENTER NORMAN OK 1010 PM CDT SUN APR 23 2006 AREAS AFFECTED...NERN CO...WRN NEB...NWRN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240310Z - 240445Z THREAT FOR ELEVATED SUPERCELLS WITH LARGE HAIL APPEARS TO BE INCREASING ACROSS NERN CO THIS EVENING. DYNAMICS AND INSTABILITY SHOULD SUPPORT THE EVOLUTION OF A SMALL MCS ACROSS THE NWRN KS/SWRN NEB BORDER AREA OVER THE NEXT FEW HOURS. A WATCH WILL BE ISSUED SHORTLY. ..CARBIN.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GID...LBF...GLD...BOU... 39100023 39670288 41040228 40469964  From Mcd at goshenarc.org Mon Apr 24 06:30:07 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 02:30:07 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240627 SWOMCD SPC MCD 240627 KSZ000-OKZ000-240830- MESOSCALE DISCUSSION 0634 NWS STORM PREDICTION CENTER NORMAN OK 0127 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS S-CENTRAL/SERN KS...N-CENTRAL-NERN OK. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 240627Z - 240830Z TSTMS MAY CONTINUE TO INCREASE IN COVERAGE ON BOTH SIDES OF KS/OK BORDER...N OF OUTFLOW BOUNDARY LEFT BEHIND BY MCS THAT NOW IS DECAYING OVER SRN MO. MAIN THREAT SHOULD BE LARGE HAIL. GUST POTENTIAL BECOMES LARGER WITH SWD EXTENT THROUGH DISCUSSION AREA...AND PROXIMITY TO OUTFLOW BOUNDARY. 61 KT GUST WAS MEASURED IN WOODWARD COUNTY OK AT 540Z. 6Z SFC ANALYSIS INDICATES OUTFLOW BOUNDARY FROM SERN DELAWARE COUNTY OK SWWD TO LINCOLN COUNTY...THEN NWWD ACROSS LOGAN/GARFIELD COUNTIES TO VICINITY NRN MAJOR/EXTREME SERN WOODS COUNTY. BOUNDARY WILL CONTINUE TO MOVE SEWD ACROSS NERN OK THROUGH AT LEAST 8Z. HOWEVER...IT SHOULD STALL SOON FROM LINCOLN COUNTY NWWD TO NEAR END...AND ALREADY HAS BECOME NEARLY STATIONARY FARTHER W. BAND OF TSTMS IS BECOMING BETTER ORGANIZED FROM PORTIONS PRATT COUNTY KS SWD TO WRN MAJOR COUNTY OK AND SHOULD CONTINUE MOVING EWD ALONG BOTH SIDES KS/OK BORDER. ANOTHER BAND OF CONVECTION IS EVIDENT FROM STAFFORD COUNTY KS SEWD TO KAY COUNTY OK...IN ZONE OF 850 MB WIND SHIFT AND APPARENT ISENTROPIC ASCENT MAX. MOST ACTIVITY SHOULD REMAIN ALONG AND N OF OUTFLOW BOUNDARY...IN REGIME OF ELEVATED LOW LEVEL WAA AIDED BY 40-50 KT LLJ EVIDENT IN VWP DATA. MODIFIED RUC SOUNDINGS INDICATE MIDLEVEL LAPSE RATES APCHG 9 DEG C/KM...ALONG WITH 850 MB DEW POINTS 13.5-15 DEG C...SUPPORTING ELEVATED MUCAPES 2000-3000 J/KG ROOTED AT TOP OF OUTFLOW AIR...WHICH DEEPENS WITH NWD EXTENT. 30-40 KT EFFECTIVE SHEAR PROFILES SHOULD AID IN STORM ORGANIZATION...MAINLY MULTICELLULAR IN CHARACTER. STRONG CINH EVIDENT S OF OUTFLOW AIR MASS SHOULD PRECLUDE SIGNIFICANT SWD PROPAGATION/BACKBUILDING OF THIS ACTIVITY. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...TOP...ICT...OUN...DDC... 36119939 36709876 37319883 38249896 38399866 38339652 38069545 37599495 36769520 36259635 36199874 WWWW From Mcd at goshenarc.org Mon Apr 24 07:08:18 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 03:08:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 240705 SWOMCD SPC MCD 240705 KSZ000-NEZ000-COZ000-240830- MESOSCALE DISCUSSION 0635 NWS STORM PREDICTION CENTER NORMAN OK 0205 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS NWRN KS...NERN CO...SWRN NEB. CONCERNING...SEVERE THUNDERSTORM WATCH 241... VALID 240705Z - 240830Z SFC MESOANALYSIS SHOWS PRIMARY LOW OVER SERN CO...SE OF STRONG BARRIER-FLOW SURGE OF RELATIVELY COLD/STABLE SFC AIR. FALLING PRESSURES IN LEE-SIDE COLD SURGE INDICATE IT SHOULD WEAKEN OVER NEXT FEW HOURS...HOWEVER ASSOCIATED BAROCLINICITY IS EVIDENT FROM SFC LOW NNEWD INTO WEAKENING CONVECTIVE CLUSTER OVER SWRN NEB. UPSTREAM 850 MB FLOW IS VEERING WITH EMPHASIS SHIFTING TOWARD MORE FAVORABLE ASCENT FOR CONVECTION ACROSS CENTRAL NEB. PER COORDINATION W/LBF...CHASE/HAYES/FRONTIER COUNTIES ARE BEING CLEARED FROM WW. GIVEN CURRENT TRENDS AND DIMINISHING PROBABILITIES FOR ADDITIONAL DEVELOPMENT ELSEWHERE WITHIN ORIGINAL WW...REMAINING PORTIONS WW MAY BE CANCELLED AND/OR ALLOWED TO EXPIRE AS SCHEDULED AT 9Z. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...GID...LBF...DDC...GLD... 39409960 38950035 38780174 39040233 40350207 40850109 40799982 40479942 WWWW From Mcd at goshenarc.org Mon Apr 24 12:34:56 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 08:34:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241232 SWOMCD SPC MCD 241232 KSZ000-OKZ000-241400- MESOSCALE DISCUSSION 0636 NWS STORM PREDICTION CENTER NORMAN OK 0732 AM CDT MON APR 24 2006 AREAS AFFECTED...PORTIONS N-CENTRAL/NERN OK...S-CENTRAL/SERN KS. CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 241232Z - 241400Z LARGE HAIL POTENTIAL HAS INCREASED ONCE AGAIN ACROSS KS/OK BORDER REGION...AND MAY PROPAGATE SWD TOWARD I-35 CORRIDOR N OF OKC GIVEN CONVECTIVE TRENDS. AREA IS BEING MONITORED FOR POSSIBLE WW. SFC MESOANALYSIS SHOWS OLD OUTFLOW BOUNDARY FROM NEAR FSM WNWWD THROUGH LOGAN...KINGFISHER...WOODWARD COUNTIES OK...DRIFTING NWD W OF I-35. REINFORCING OUTFLOW AIR EXTENDS FROM NERN OK/NWRN AR CONVECTION WNWWD ACROSS PORTIONS SRN OSAGE COUNTY TO GRANT COUNTY...WITH WHICH ONE STORM IS INTERACTING AND SHOWING SOME EVIDENCE OF ROTATION ALOFT. OTHER TSTMS HAVE DEVELOPED RAPIDLY FROM ICT AREA SSWWD THROUGH KINGFISHER COUNTY OK. IR IMAGERY AND REFLECTIVITY DATA INDICATE LINE MAY SOLIDIFY SSWWD INTO CANADIAN COUNTY. THIS ACTIVITY SHOULD CONTINUE TO MOVE EWD ACROSS N-CENTRAL OK AND S-CENTRAL KS...WITH FAVORABLE VERTICAL SHEAR PROFILES FOR STORM ROTATION AND ENHANCED LARGE HAIL POTENTIAL. 35-50 KT EFFECTIVE SHEAR IS EVIDENT...DEPENDING ON CHOSEN LIFTED LAYER...WITH PARCELS LIKELY ROOTED AROUND 850 MB. FAVORABLE THERMODYNAMIC ENVIRONMENT OF ELEVATED WAA AND STEEP MIDLEVEL LAPSE RATES NEAR 9 DEG C/KM...YIELDS ELEVATED MUCAPES 1500-2500 J/KG...BASED ON MODIFIED RAOB DATA AND RUC FCST SOUNDINGS. ..EDWARDS.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...TOP...ICT...OUN... 35879803 36689762 37499742 38029749 38249658 38249602 38109526 37769501 36829516 35599656 35689766 WWWW From Mcd at goshenarc.org Mon Apr 24 16:11:43 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 12:11:43 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241609 SWOMCD SPC MCD 241608 OKZ000-KSZ000-241745- MESOSCALE DISCUSSION 0637 NWS STORM PREDICTION CENTER NORMAN OK 1108 AM CDT MON APR 24 2006 AREAS AFFECTED...EXTREME SERN KS INTO NERN OK CONCERNING...SEVERE THUNDERSTORM WATCH 242... VALID 241608Z - 241745Z THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL MAY PERSIST ANOTHER COUPLE HOURS OR SO ACROSS NERN OK AS STORMS DEVELOP SLOWLY SWD. EARLY THIS MORNING A CLUSTER OF STORMS CONTINUES OVER NERN OK INTO SERN KS N OF A CONVECTIVE OUTFLOW BOUNDARY THAT CURRENTLY EXTENDS FROM CNTRL OK NWWD INTO NWRN OK. THE LOW LEVEL JET THAT CONTRIBUTED TO STRONG LIFT N OF THE OUTFLOW BOUNDARY HAS WEAKENED CONSIDERABLY OVER THE LAST FEW HOURS...AND MOST OF THE DISCRETE STORMS HAVE DISSIPATED. PRIMARY CONVECTIVE MODE HAS TRANSITIONED TO A CLUSTER OF STORMS OVER NERN OK THAT APPEARS TO BE PROPAGATING SWD ALONG THE CONVECTIVELY ENHANCED OUTFLOW BOUNDARY. NEW CELLS ARE ALSO DEVELOPING ALONG THE SWRN FLANKS OF THE CONVECTION AT THE INTERSECTION OF TWO OUTFLOW BOUNDARIES. THE ATMOSPHERE SW OF THIS ACTIVITY IS MODERATELY UNSTABLE WITH MLCAPE AROUND 2000 J/KG. THE LATEST OBJECTIVE ANALYSIS STILL SHOWS FAIRLY STRONG SURFACE BASED CONVECTIVE INHIBITION AND RAISES UNCERTAINTY HOW LONG THE STORMS WILL PERSIST. HOWEVER...AS THE BOUNDARY LAYER CONTINUES TO WARM AND THE CAP WEAKENS...STORMS ON THE SWRN FLANKS OF THIS ACTIVITY MAY CONTINUE TO DEVELOP SWD NEXT COUPLE HOURS. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN... 35759685 36619774 37149691 37149529 36059510 WWWW From Mcd at goshenarc.org Mon Apr 24 18:16:12 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 14:16:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241813 SWOMCD SPC MCD 241813 OKZ000-KSZ000-242015- MESOSCALE DISCUSSION 0638 NWS STORM PREDICTION CENTER NORMAN OK 0113 PM CDT MON APR 24 2006 AREAS AFFECTED...W CNTRL THROUGH NWRN OK INTO SWRN KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 241813Z - 242015Z THUNDERSTORMS ARE EXPECTED TO DEVELOP IN A CORRIDOR FROM SWRN KS SWD INTO W CNTRL AND POSSIBLY SWRN OK BY MID AFTERNOON. SUPERCELLS WITH VERY LARGE HAIL AND A FEW TORNADOES WILL BE THE PRIMARY THREATS. TORNADO WATCH WILL LIKELY BE ISSUED WITHIN THE NEXT HOUR OR TWO. AN OUTFLOW BOUNDARY EXTENDS FROM NERN OK WWD TO A SURFACE LOW IN NWRN OK. ANOTHER MORE SUBTLE OUTFLOW BOUNDARY EXTENDS FROM E CNTRL OK NWWD INTO NWRN OK. A DRY LINE EXTENDS SWD FROM THE LOW THROUGH EXTREME WRN OK INTO NWRN TX. A COLD FRONT EXTENDS FROM NERN KS SWWD THROUGH SWRN KS AND FROM THE SURFACE LOW IN NWRN OK SWWD THROUGH THE TX PANHANDLE. THE ATMOSPHERE S OF THESE BOUNDARIES IS BECOMING VERY UNSTABLE. AMPLE SURFACE HEATING...RICH LOW LEVEL MOISTURE AND MID LEVEL LAPSE RATES AROUND 8.5 C/KM WILL SUPPORT MLCAPE FROM 3000 TO 3500 J/KG THIS AFTERNOON. A MID LEVEL JET MAX WILL ROTATE THROUGH THE BASE OF A SHORTWAVE TROUGH NOW OVER THE SRN ROCKIES NEWD INTO THE SRN AND CNTRL PLAINS THIS AFTERNOON AND EVENING WITH ATTENDANT HEIGHT FALLS. AS THIS OCCURS...THE SURFACE LOW IS FORECAST TO BECOME FOCUSED A LITTLE FARTHER SWD ACROSS W CNTRL OR SWRN OK LATER THIS AFTERNOON. THIS SUGGESTS THE LOW LEVEL FLOW SHOULD REMAIN BACKED TO SLY OVER CNTRL AND W CNTRL OK AHEAD OF THE DRYLINE. RECENT VWP DATA HAS SHOWN THE FLOW IN THE 1 TO 2 KM LAYER HAS BACKED DURING THE PAST HOUR ACROSS CNTRL OK. VISIBLE IMAGERY SHOWS CUMULUS INCREASING FROM NEAR THE TRIPLE POINT IN NWRN OK SWD THROUGH WRN OK ALONG AND E OF THE DRYLINE. STORMS ARE EXPECTED TO DEVELOP IN VICINITY OF THE TRIPLE POINT OVER NWRN OK AND SWRN KS AND SWD SOME DISTANCE ALONG THE DRYLINE WITHIN THE NEXT 2-3 HOURS AS THE CAP CONTINUES TO WEAKEN. DEEP LAYER SHEAR WILL INCREASE AND BECOME SUPPORTIVE OF SUPERCELLS AS THE MID LEVEL SPEED MAX ADVANCES EWD. GIVEN THE VERY FAVORABLE THERMODYNAMIC PROFILES AND LIKELIHOOD FOR SUPERCELLS...VERY LARGE HAIL WILL BE LIKELY. BEST TORNADO THREAT APPEARS TO BE ACROSS PARTS OF NWRN AND CNTRL OK INTO SWRN KS WHERE STORMS WILL HAVE THE OPPORTUNITY TO INTERACT WITH MODIFYING OUTFLOW BOUNDARIES. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ICT...OUN...DDC... 34919704 34509864 35769893 37059962 37419964 37489874 36539756 35749685 WWWW From Mcd at goshenarc.org Mon Apr 24 19:17:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 15:17:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 241914 SWOMCD SPC MCD 241914 ARZ000-MOZ000-OKZ000-242015- MESOSCALE DISCUSSION 0639 NWS STORM PREDICTION CENTER NORMAN OK 0214 PM CDT MON APR 24 2006 AREAS AFFECTED...ERN OK THROUGH NRN AND CNTRL AR CONCERNING...SEVERE THUNDERSTORM WATCH 243... VALID 241914Z - 242015Z STORMS ARE EXPECTED TO CONTINUE DEVELOPING SEWD THROUGH ERN OK INTO NRN AND CNTRL AR NEXT FEW HOURS. LARGE HAIL AND ISOLATED DAMAGING WIND WILL BE THE PRIMARY THREATS. A NEW WW WILL LIKELY BE NEEDED FOR PORTIONS OF ERN OK INTO WRN AR WITHIN THE NEXT HOUR OR SO. THIS AFTERNOON A LINE OF SEVERE STORMS FROM NERN OK INTO NWRN AR CONTINUES SEWD. THE LINE HAS TRANSITIONED TO A FORWARD PROPAGATING MCS...AND THE ATMOSPHERE DOWNSTREAM ACROSS NWRN AR AND ERN OK HAS BECOME MODERATELY UNSTABLE WITH MLCAPE FROM 2000 TO 2500 J/KG. LOW LEVEL CONVERGENCE AND LIFT ALONG THE GUST FRONT ALONG WITH WEAKENING CONVECTIVE INHIBITION SHOULD SUSTAIN THE MCS THROUGH ERN OK NRN AR NEXT FEW HOURS. STEEP MID LEVEL LAPSE RATES...STRONG INSTABILITY AND SUFFICIENT CLOUD LAYER SHEAR FOR EMBEDDED SUPERCELLS WILL CONTINUE TO SUPPORT A THREAT FOR LARGE HAIL. ISOLATED DAMAGING WIND GUSTS MAY ALSO ACCOMPANY THE STRONGER STORMS. ..DIAL.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...SGF...TSA... 35849585 36519407 36319102 34579194 34799514 WWWW From Mcd at goshenarc.org Mon Apr 24 20:21:35 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 16:21:35 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242018 SWOMCD SPC MCD 242018 MOZ000-KSZ000-NEZ000-242215- MESOSCALE DISCUSSION 0641 NWS STORM PREDICTION CENTER NORMAN OK 0318 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/EASTERN KS INTO FAR WESTERN MO CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242018Z - 242215Z SEVERE POTENTIAL /WITH PRIMARY HAZARD OF LARGE HAIL/ IS EXPECTED TO INCREASE OVER THE NEXT FEW HOURS ACROSS NORTH CENTRAL/EASTERN KS...AND PERHAPS FAR WESTERN MO/FAR SOUTHEAST NEB. A WATCH MAY BE NEEDED IN THE NEXT HOUR OR TWO. THUNDERSTORM COVERAGE IS EXPECTED TO INCREASE ACROSS MUCH OF NORTH CENTRAL INTO EASTERN KS...AND PERHAPS ADJACENT PORTIONS OF FAR SOUTHEAST NEB/WESTERN MO...THROUGH LATE AFTERNOON AND EARLY EVENING. THIS ACTIVITY IS LIKELY BOTH IN VICINITY OF THE SOUTHWEST-NORTHEAST ORIENTED FRONTAL ZONE FROM WEST CENTRAL KS INTO WEST CENTRAL IA...BUT ALSO WITH WARM ADVECTION ATOP THE RESIDUAL COLD POOL ACROSS EASTERN KS VIA EARLY DAY CONVECTION. WITHIN THIS CORRIDOR...POTENTIAL FOR SURFACE CONVECTION APPEARS LIMITED...ESPECIALLY WITH NORTHWARD EXTENT. ACCORDINGLY...ELEVATED CONVECTIVE MODE WILL LIKELY BE PREDOMINANT...WITH A PRIMARY HAZARD OF LARGE HAIL. RUC PROXIMITY SOUNDINGS PORTRAY ELEVATED MUCAPE OF 500-1000 J/KG IN PRESENCE OF STEEP MID LEVEL LAPSE RATE/STRONG CLOUD BEARING SHEAR ENVIRONMENT...FAVORABLE FOR AT LEAST ISOLATED LARGE HAIL. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EAX...OAX...TOP...ICT... 38989797 39429786 40229640 39479415 38339390 37949573 38399728 WWWW From Mcd at goshenarc.org Mon Apr 24 22:30:15 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 18:30:15 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242227 SWOMCD SPC MCD 242216 TXZ000-OKZ000-250015- MESOSCALE DISCUSSION 0642 NWS STORM PREDICTION CENTER NORMAN OK 0516 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242216Z - 250015Z MONITORING FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS NORTH CENTRAL INTO WEST CENTRAL TX...A CONDITIONAL POTENTIAL FOR VERY LARGE HAIL EXISTS. A SEVERE THUNDERSTORM WATCH COULD BE NEEDED IN THE NEXT HOUR OR TWO. ALTHOUGH REGION IS ON SOUTHERN FRINGE OF PRIMARY BACKGROUND FORCING FOR ASCENT/STRONGER MID LEVEL FLOW...AT LEAST ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP ACROSS NORTH CENTRAL INTO WEST CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. ALTHOUGH BOUNDARY LAYER CU HAS BEEN MODEST THUS FAR...VISIBLE TRENDS OVER THE PAST HALF HOUR FEATURES ISOLATED POCKETS OF MORE AGGRESSIVE CU...PERHAPS TIED TO A SUBTLE UPPER IMPULSE PER WATER VAPOR IMAGERY. ADJUSTED RUC SOUNDINGS/OBJECTIVE ANALYSIS SUGGESTS CONVECTIVE INHIBITION IS VIRTUALLY NIL IN VICINITY OF THE DRYLINE ACROSS NORTH CENTRAL/WEST CENTRAL TX...ROUGHLY LOCATED FROM NEAR ALTUS OK/WEST OF WICHITA FALLS TX...TO NEAR BROWNWOOD AND JUNCTION TX. WEST OF THE DRYLINE...DEEPLY MIXED PLUME WITH LOW TO MID 90S F TEMPERATURES IS IMPINGING UPON DEEPER MOISTURE EAST OF THE DRYLINE IN CENTRAL TX...CHARACTERIZED BY BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S/LOWER 70S. RUC PROXIMITY SOUNDINGS SUGGEST POTENTIAL FOR MLCAPE IN EXCESS OF 3000 J/KG. OBSERVED TRENDS IN THE JAYTON TX PROFILER CAPTURE MODEST INCREASE IN MID LEVEL WINDS OVER THE PAST FEW HOURS...WITH AROUND 40 KTS SOUTHWESTLY WINDS NOTED IN THE 4-6 KM LAYER AND ABOVE. GIVEN THE DEGREE OF INSTABILITY/ADEQUATE SHEAR...SUPERCELLS ARE LIKELY PROVIDED CONVECTIVE INITIATION...WITH POTENTIAL FOR VERY LARGE HAIL. A SEVERE WATCH MAY BE PRUDENT IN THE NEXT FEW HOURS...ESPECIALLY IF CONFIDENCE IN CONVECTIVE INITIATION/SCATTERED STORM COVERAGE INCREASES. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 30839846 30309926 30640019 31279972 32039927 32599920 34109902 33859780 33279748 32009760 31449794 WWWW From Mcd at goshenarc.org Mon Apr 24 22:32:39 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 18:32:39 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242229 SWOMCD SPC MCD 242229 TXZ000-OKZ000-250030- MESOSCALE DISCUSSION 0642 NWS STORM PREDICTION CENTER NORMAN OK 0529 PM CDT MON APR 24 2006 AREAS AFFECTED...NORTH CENTRAL/WEST CENTRAL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 242229Z - 250030Z MONITORING FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON/EARLY EVENING ACROSS NORTH CENTRAL INTO WEST CENTRAL TX...A CONDITIONAL POTENTIAL FOR VERY LARGE HAIL EXISTS. A SEVERE THUNDERSTORM WATCH COULD BE NEEDED IN THE NEXT HOUR OR TWO. ALTHOUGH REGION IS ON SOUTHERN FRINGE OF PRIMARY BACKGROUND FORCING FOR ASCENT/STRONGER MID LEVEL FLOW...AT LEAST ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP ACROSS NORTH CENTRAL INTO WEST CENTRAL TX LATE THIS AFTERNOON/EARLY EVENING. ALTHOUGH BOUNDARY LAYER CU HAS BEEN MODEST THUS FAR...VISIBLE TRENDS OVER THE PAST HALF HOUR FEATURES ISOLATED POCKETS OF MORE AGGRESSIVE CU...PERHAPS TIED TO A SUBTLE UPPER IMPULSE PER WATER VAPOR IMAGERY. ADJUSTED RUC SOUNDINGS/OBJECTIVE ANALYSIS SUGGESTS CONVECTIVE INHIBITION IS VIRTUALLY NIL IN VICINITY OF THE DRYLINE ACROSS NORTH CENTRAL/WEST CENTRAL TX...ROUGHLY LOCATED FROM NEAR ALTUS OK/WEST OF WICHITA FALLS TX...TO NEAR BROWNWOOD AND JUNCTION TX. WEST OF THE DRYLINE...DEEPLY MIXED PLUME WITH LOW TO MID 90S F TEMPERATURES IS IMPINGING UPON DEEPER MOISTURE EAST OF THE DRYLINE IN CENTRAL TX...CHARACTERIZED BY BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S/LOWER 70S. RUC PROXIMITY SOUNDINGS SUGGEST POTENTIAL FOR MLCAPE IN EXCESS OF 3000 J/KG. OBSERVED TRENDS IN THE JAYTON TX PROFILER CAPTURE MODEST INCREASE IN MID LEVEL WINDS OVER THE PAST FEW HOURS...WITH AROUND 40 KTS SOUTHWESTLY WINDS NOTED IN THE 4-6 KM LAYER AND ABOVE. GIVEN THE DEGREE OF INSTABILITY/ADEQUATE SHEAR...SUPERCELLS ARE LIKELY PROVIDED CONVECTIVE INITIATION...WITH POTENTIAL FOR VERY LARGE HAIL. A SEVERE WATCH MAY BE PRUDENT IN THE NEXT FEW HOURS...ESPECIALLY IF CONFIDENCE IN CONVECTIVE INITIATION/SCATTERED STORM COVERAGE INCREASES. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FWD...OUN...EWX...SJT... 30839846 30309926 30640019 31279972 32039927 32599920 34109902 33859780 33279748 32009760 31449794 WWWW From Mcd at goshenarc.org Mon Apr 24 23:20:37 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 19:20:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 242317 SWOMCD SPC MCD 242317 KSZ000-OKZ000-250045- MESOSCALE DISCUSSION 0644 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CDT MON APR 24 2006 AREAS AFFECTED...SOUTH CENTRAL KS AND WESTERN/CENTRAL OK CONCERNING...TORNADO WATCH 244... VALID 242317Z - 250045Z VALID PORTION OF TORNADO WATCH 244 CONTINUES UNTIL 02Z...WITH INCREASING POTENTIAL FOR VERY LARGE HAIL AND TORNADOES. SEVERE THUNDERSTORMS ARE ONGOING JUST EAST OF THE I-35 CORRIDOR IN SOUTH CENTRAL KS AND NORTH CENTRAL OK...FROM EAST OF WICHITA KS TO NEAR STILLWATER OK. MAIN HAZARD WITH THESE STORMS IN THE SHORT TERM WILL BE LARGE HAIL AS STORMS BEGIN TO OVERSPREAD RESIDUAL COLD POOL INTO SOUTHEAST KS/NORTHEAST OK. PRIMARY TORNADO POTENTIAL ACROSS TORNADO WATCH 244 SEEMINGLY REMAINS WITH STORMS THAT DEVELOP/MOVE EAST-NORTHEAST AND INTERACT WITH RESIDUAL OUTFLOW BOUNDARY ACROSS NORTH CENTRAL OK...ROUGHLY FROM NEAR ALVA/ENID OK TO JUST NORTH OF THE OKC METRO AREA. IN SOUTHWEST/WEST CENTRAL OK...RAPID THUNDERSTORM DEVELOPMENT IS OCCURRING ACROSS CADDO/COMANCHE/TILLMAN COUNTIES AS OF 2310Z. VERY MOIST/UNCAPPED AIRMASS IS IN PLACE AHEAD OF THESE STORMS INTO CENTRAL OK...THUS FURTHER DEVELOPMENT/SHORT TERM INTENSIFICATION APPEARS LIKELY AHEAD OF THE DRYLINE/COLD FRONT. AMBIENT WARM SECTOR AIRMASS IS CHARACTERIZED BY MLCAPE IN EXCESS OF 3000 J/KG. IN ADDITION...LOW LEVEL FLOW HAS BACKED TO SOUTH/SOUTHEAST OVER THE PAST FEW HOURS ACROSS CENTRAL/SOUTHWEST OK. ASIDE FROM VERY LARGE HAIL...MODESTLY ENLARGED LOW LEVEL HODOGRAPHS PER ADJUSTED TLX WSR-88D VAD IS SUFFICIENT FOR LOW LEVEL STORM ROTATION/POTENTIAL TORNADOES AS STORMS INTENSIFY/MOVE EAST-NORTHEAST INTO CENTRAL OK. ..GUYER.. 04/24/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN...DDC... 37629849 37919818 38159753 37789660 36619637 35639671 34429702 34159790 34359880 35509895 36759870 37269863 WWWW From Mcd at goshenarc.org Tue Apr 25 01:30:28 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 21:30:28 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250127 SWOMCD SPC MCD 250127 OKZ000-KSZ000-TXZ000-250200- MESOSCALE DISCUSSION 0645 NWS STORM PREDICTION CENTER NORMAN OK 0827 PM CDT MON APR 24 2006 AREAS AFFECTED...KS...OK CONCERNING...TORNADO WATCH 244...246... VALID 250127Z - 250200Z INTENSE SUPERCELLS MOVING ACROSS CNTRL/NERN OK EXPECTED TO CONTINUE TO POSE A THREAT OF VERY LARGE HAIL...DAMAGING WINDS...AND PERHAPS A TORNADO OR TWO. A NEW TORNADO WATCH REPLACING PORTIONS OF WW 244 AND WW 246 ACROSS CNTRL AND NERN OK WILL BE ISSUED SHORTLY. ENVIRONMENT AHEAD OF ONGOING LONG-TRACK SUPERCELLS...FROM OSAGE COUNTY AND TULSA AREA SWWD ACROSS OKLAHOMA CITY METRO AND POINTS SOUTH...WILL CONTINUE TO SUPPORT STRONG STORM ROTATION GIVEN ABUNDANT INSTABILITY AND STRONG SHEAR. ACTIVITY CROSSING THE RESIDUAL OUTFLOW BOUNDARY ACROSS NERN OK APPEARS TO BE DEVELOPING UPSCALE AND INTO A LARGER MCS WITH POTENTIAL FOR WIND DAMAGE DEVELOPING INTO THE TULSA AREA INCREASING. OTHER STORMS...AHEAD OF THE DRYLINE...REMAIN DISCRETE AND LONG-LIVED WITH OCCASIONAL MESOCYCLONES CONTINUING TO APPEAR IN SRM LOOPS FROM AREA RADAR. A CONTINUING THREAT FOR VERY LARGE HAIL AND ISOLATED BRIEF TORNADOES WILL PERSIST WITH THIS ACTIVITY AS IT DEVELOPS EWD AT 15-20KT. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...ICT...OUN... 34109696 34159908 35099927 35019840 36189865 37109819 38349798 38319722 37269672 36639653 35209664 WWWW From Mcd at goshenarc.org Tue Apr 25 03:33:40 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Mon, 24 Apr 2006 23:33:40 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250331 SWOMCD SPC MCD 250330 ARZ000-MOZ000-OKZ000-KSZ000-TXZ000-250500- MESOSCALE DISCUSSION 0646 NWS STORM PREDICTION CENTER NORMAN OK 1030 PM CDT MON APR 24 2006 AREAS AFFECTED...SRN TO NERN OK CONCERNING...TORNADO WATCH 247... VALID 250330Z - 250500Z EXPECT PRE-FRONTAL LINEAR MCS OVER NERN OK TO CONTINUE TO WEAKEN AS ACTIVITY INGESTS GREATER STABILITY ON THE COOL SIDE OF RESIDUAL OUTFLOW BOUNDARY. THIS LINE WAS MOVING EAST AT UP TO 35KT IN SOME AREAS SO A MARGINAL SEVERE WIND AND HAIL THREAT MAY STILL EXIST ACROSS VALID PORTIONS OF THE WATCH FOR ANOTHER HOUR OR SO. A FEW INTENSE STORMS WITH LARGE HAIL AND WEAK/BRIEF TORNADO THREAT REMAIN POSSIBLE IN THE WARM SECTOR SOUTH OF OKC AREA. IN ADDITION TO LONG-LIVED SUPERCELL OVER GARVIN AND PONTOTOC COUNTIES...ADDITIONAL STORMS APPEAR TO BE FORMING ALONG THE COLD FRONT NOW MOVING EAST TOWARD I35/I44. AIR MASS AHEAD OF THIS CONVECTION REMAINS VERY UNSTABLE AND SHEAR WILL CONTINUE TO SUPPORT UPDRAFT INTENSIFICATION. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SGF...TSA...ICT...FWD...OUN... 34009797 34129837 35779684 36469661 37029640 36669588 36589532 36659463 35429439 35059490 34989554 34659550 34189576 33889659 33819713 33879798 WWWW From Mcd at goshenarc.org Tue Apr 25 06:06:41 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 02:06:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250604 SWOMCD SPC MCD 250603 ARZ000-250800- MESOSCALE DISCUSSION 0647 NWS STORM PREDICTION CENTER NORMAN OK 0103 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS WRN...CENTRAL AND NRN AR. CONCERNING...CONVECTIVE TRENDS VALID 250603Z - 250800Z SEVERE POTENTIAL SHOULD DIMINISH WITH NWRN AR COMPLEX...THEREFORE ADDITIONAL WW NOT ANTICIPATED ATTM IN ITS PROJECTED PATH. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY -- LEFT BEHIND BY AFTERNOON MCS -- FROM NEAR PBF WNWWD ACROSS LATIMER/PUSHMATAHA COUNTY LINE. LINE OF TSTMS -- NOW MOVING ESEWD 40-45 KT ACROSS NERN AR -- IS EXPECTED TO MOVE INTO MORE STABLE AIR MASS ALOFT ACROSS CENTRAL/N-CENTRAL AR AND WEAKEN. ITS OWN OUTFLOW ALREADY HAS SURGED 10-20 NM AHEAD OF LEADING EDGE OF STRONGEST REFLECTIVITIES...AS EVIDENT IN ANIMATED REFLECTIVITY IMAGERY FROM FSM. THERE MAY STILL BE OCCASIONAL GUSTS BELOW 50 KT SEVERE CRITERIA -- BUT CAPABLE OF DAMAGE TO TREES AND WEAK STRUCTURES -- ALONG WITH INTERMITTENT/MRGLLY SEVERE HAIL. ACTIVITY IS ROOTED IN LAYER OF ELEVATED BUOYANCY ATOP OLDER OUTFLOW BOUNDARY...ELEVATED MUCAPES DIMINISHING FROM AROUND 1500 J/KG ALONG OK/AR BORDER...TO LESS THAN 500 J/KG FROM LIT EWD. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MEG...LZK...TSA... 35119441 35509353 35989313 36389287 36179142 35779098 34799158 34559302 34909414 WWWW From Mcd at goshenarc.org Tue Apr 25 06:14:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 02:14:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250612 SWOMCD SPC MCD 250611 ARZ000-TXZ000-OKZ000-250715- MESOSCALE DISCUSSION 0648 NWS STORM PREDICTION CENTER NORMAN OK 0111 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS SERN OK...NE TX...SWRN AR. CONCERNING...TORNADO WATCH 247... VALID 250611Z - 250715Z ORGANIZED SEVERE POTENTIAL MAY LINGER WITH TSTM CLUSTER EVIDENT AT 545Z OVER PORTIONS COAL/SRN PITTSBURG/NWRN ATOKA COUNTIES. THIS ACTIVITY SHOULD MOVE EWD/ESEWD ACROSS SERN OK WITH SOME POTENTIAL TO BACKBUILD TOWARD RED RIVER VALLEY BEFORE ENTERING AR. REPLACEMENT WW MAY BE NEEDED SOON. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY -- LEFT BEHIND BY AFTERNOON MCS -- FROM NEAR PBF WNWWD ACROSS LATIMER/PUSHMATAHA COUNTY LINE. SFC COLD FRONT IS ANALYZED FROM TUL AREA SWWD ACROSS GARVIN COUNTY...THEN NEAR SPS. FRONT SHOULD CONTINUE MOVING SEWD 10-20 KT. AXIS OF MAX 850 MB MOISTURE TRANSPORT IS PROGGED TO SHIFT EWD WITH VEERING LLJ TOWARD CHOCTAW/MCCURTAIN COUNTIES...IN AGREEMENT WITH CORFIDI-MCS MOTION VECTORS INDICATING SLOW TRACK THAT WAY. EXPECT INFLOW LAYER FOR SERN OK COMPLEX TO BECOME PROGRESSIVELY MORE ELEVATED AGL THROUGH REMAINDER TONIGHT. HOWEVER...MODIFIED RAOBS AND RUC SOUNDING DATA INDICATES SOME PARCELS ACROSS S-CENTRAL/SERN OK -- AHEAD OF COLD FRONT AND GENERALLY S-SW OF ONGOING ACTIVITY -- REMAIN NEARLY SFC-BASED. ANY ACTIVITY DEVELOPING FARTHER NW AND N IN WW 247 MAY PRODUCE OCNL HAIL NEAR SEVERE LEVELS...BUT NOT TORNADOES BECAUSE OF ITS MORE ELEVATED/DISORGANIZED CHARACTER. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 34409695 35529627 35689554 35399462 35239419 34979404 34599396 34449393 34229406 33849424 33539468 33489512 33469583 33609655 WWWW From Mcd at goshenarc.org Tue Apr 25 10:01:09 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 06:01:09 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 250958 SWOMCD SPC MCD 250957 ARZ000-TXZ000-OKZ000-251200- MESOSCALE DISCUSSION 0649 NWS STORM PREDICTION CENTER NORMAN OK 0457 AM CDT TUE APR 25 2006 AREAS AFFECTED...PORTIONS N-CENTRAL/NE TX...S-CENTRAL/SERN OK...SWRN-CENTRAL AR. CONCERNING...SEVERE THUNDERSTORM WATCH 248... VALID 250957Z - 251200Z CURRENT CONVECTIVE TRENDS AND MODIFIED SOUNDINGS INDICATE DIMINISHING SEVERE POTENTIAL OVER WW AREA...AND ALSO...WITH EWD EXTENT ACROSS AR AHEAD OF ONGOING MCS. ACCORDINGLY...PORTIONS WW MAY BE CANCELED BEFORE SCHEDULED 12Z EXPIRATION. MEANWHILE...WW SHOULD BE CLEARED BEHIND FROPA. SFC ANALYSIS INDICATES COLD FRONT AT 930Z FROM JACK/COOKE COUNTIES TX NEWD THROUGH HUGHES COUNTY OK...BECOMING DIFFUSE FARTHER N AMIDST BLEND OF CONVECTIVE OUTFLOWS. EXPECT LOW LEVEL AIR MASS TO STABILIZE BEHIND THIS FRONT FROM W-E AND TO BECOME PROGRESSIVELY LESS CONDUCIVE FOR SVR TSTM DEVELOPMENT. MEANWHILE...MCS HAS EXITED ERN PORTIONS WW...AND REMAINS LARGELY BELOW SEVERE LEVELS AS IT MOVES EWD ACROSS WRN/CENTRAL AR ATTM. MODIFIED RAOBS AND RUC SOUNDINGS INDICATE STRONG MERIDIONAL GRADIENT IN ELEVATED BUOYANCY REMAINS ACROSS CENTRAL AR. COMPLEX SOON WILL MOVE INTO ENVIRONMENT MUCH MORE HOSTILE FOR SUSTAINING DEEP CONVECTION WITH MUCAPES DROPPING BELOW 500 J/KG. WIDELY SCATTERED CONVECTION MAY CONTINUE TO DEVELOP OVER ITS OWN OUTFLOW POOL OVER SERN OK...HOWEVER THIS AIR MASS WILL CONTAIN MORE ELEVATED BUOYANT LAYER WITH WEAKER CAPE THAN WAS AVAILABLE TO INITIAL ACTIVITY. STRONGER MUCAPE -- UP TO 2500 J/KG -- REMAINS E OF COLD FRONT AND S OF COLLECTIVE OUTFLOW BOUNDARY...OVER RED RIVER REGION OF SERN OK/NERN TX. STRENGTHENING CAPPING WITH SWD EXTENT...AND WEAK EFFECTIVE SHEARS OF 25 KT OR LESS OVER MUCH OF THIS REGION...LEND CONSIDERABLE DOUBT ABOUT FURTHER POTENTIAL FOR ORGANIZED SEVERE. ..EDWARDS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LZK...SHV...TSA...FWD...OUN... 34699535 34459378 34769305 35129294 35089187 34429168 33679222 33359530 33689719 WWWW From mcd at goshenarc.org Tue Apr 25 15:45:38 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 11:45:38 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251542 SWOMCD SPC MCD 251542 WVZ000-VAZ000-KYZ000-TNZ000-251745- MESOSCALE DISCUSSION 0650 NWS STORM PREDICTION CENTER NORMAN OK 1042 AM CDT TUE APR 25 2006 AREAS AFFECTED...ERN KY/ERN TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251542Z - 251745Z CONVECTIVE TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE THREAT. A WW COULD BECOME NECESSARY...PERHAPS BY EARLY AFTERNOON. MID-LEVEL CYCLONIC VORTICITY CENTER....ASSOCIATED WITH REMNANTS OF OVERNIGHT CONVECTIVE CLUSTER...IS EVIDENT IN OBSERVATIONAL DATA... MIGRATING ACROSS WESTERN KENTUCKY AT THE MOMENT. THIS FEATURE IS ON SOUTHERN PERIPHERY OF MODERATELY STRONG CONFLUENT MID-LEVEL FLOW REGIME...AND IS EXPECTED TO BECOME INCREASINGLY SHEARED AS IT ACCELERATES TOWARD THE CENTRAL APPALACHIANS. HOWEVER...FORCING IS EXPECTED TO REMAIN SUFFICIENT TO SUPPORT INCREASING CONVECTIVE DEVELOPMENT INTO THE AFTERNOON HOURS ACROSS CENTRAL/EASTERN KENTUCKY AND PARTS OF NORTHEASTERN TENNESSEE. ONGOING ACTIVITY SEEMS LIKELY TO BECOME INCREASINGLY BASED IN MOIST BOUNDARY LAYER EAST OF BOWLING GREEN SHORTLY. AND...A GRADUAL INTENSIFICATION IS EXPECTED AS INFLOW FROM A DESTABILIZING BOUNDARY LAYER ACROSS THE LEXINGTON/LONDON/SOMERSET AREAS STRENGTHENS BY 18-19Z. THIS SEEMS LIKELY TO BE ACCOMPANIED BY INCREASING POTENTIAL FOR DAMAGING SURFACE GUSTS...AIDED BY BELT OF 30 TO 40 KT WESTERLY LOWER/MID TROPOSPHERIC FLOW. STRONGER STORMS MAY ALSO PRODUCE SOME HAIL...BUT WITH CAPE GENERALLY AROUND 1000 J/KG...PEAK HAIL SIZES MAY REMAIN MARGINALLY SEVERE. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RLX...MRX...JKL...ILN...LMK...OHX... 37718582 38328513 38538426 38528328 38328240 37728197 36908231 36018339 35948465 35918570 36488624 37028604 37348591 WWWW From mcd at goshenarc.org Tue Apr 25 16:10:25 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 12:10:25 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251607 SWOMCD SPC MCD 251607 MSZ000-LAZ000-TXZ000-251730- MESOSCALE DISCUSSION 0651 NWS STORM PREDICTION CENTER NORMAN OK 1107 AM CDT TUE APR 25 2006 AREAS AFFECTED...SE TX...SRN LA...SRN MS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251607Z - 251730Z A WW IS NOT ANTICIPATED IN THE NEAR TERM...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE POTENTIAL. OUTFLOW BOUNDARY GENERATED BY OVERNIGHT CONVECTION IS ADVANCING SLOWLY SOUTHWARD THROUGH THE LOWER MISSISSIPPI VALLEY. THIS FEATURE HAS YET TO BECOME FOCUS FOR VIGOROUS NEW CONVECTIVE DEVELOPMENT...BUT BROAD LOW-LEVEL WARM ADVECTION REGIME NORTH AND SOUTH OF THE BOUNDARY IS PROVIDING SUPPORT FOR INCREASING CONVECTIVE DEVELOPMENT. MOST VIGOROUS STORMS THROUGH 17-18Z SEEM LIKELY TO EVOLVE TO THE SOUTH OF THE OUTFLOW...WITH ADDITIONAL ACTIVITY EVENTUALLY DEVELOPING ALONG THE BOUNDARY ITSELF. AS CONVECTIVE TEMPERATURES ARE APPROACHED...CONVECTION WILL BECOME ROOTED IN MIXED BOUNDARY LAYER WITH CAPE IN EXCESS OF 2000 J/KG. LOW-LEVEL WIND FIELDS ARE RATHER WEAK...BUT MID/UPPER FLOW APPEARS STRONG ENOUGH FOR DEEP LAYER SHEAR FAVORABLE FOR AT LEAST BRIEF MID-LEVEL UPDRAFT ROTATION...WHICH WILL ENHANCE POTENTIAL FOR HAIL IN STRONGER CELLS. LOCALIZED DOWNBURSTS ARE ALSO POSSIBLE. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LIX...LCH...SHV...HGX...FWD... 31049638 31759549 32359444 31919290 31979098 31939035 30818971 30118995 29889167 30029335 29899501 30159642 WWWW From mcd at goshenarc.org Tue Apr 25 18:38:23 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 14:38:23 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251835 SWOMCD SPC MCD 251835 TXZ000-252030- MESOSCALE DISCUSSION 0652 NWS STORM PREDICTION CENTER NORMAN OK 0135 PM CDT TUE APR 25 2006 AREAS AFFECTED...S-CNTRL TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251835Z - 252030Z THUNDERSTORM INITIATION APPEARS MOST PROBABLE BETWEEN 21-23Z. A WW WILL LIKELY BE NEEDED LATER THIS AFTERNOON. 18Z SURFACE ANALYSIS AND MODIFIED RUC SOUNDINGS SHOW A WEAKENING CAP ACROSS S-CNTRL TX ALONG A SYNOPTIC COLD FRONT FROM NEAR DRT NEWD TO SAT AND CLL. VISIBLE SATELLITE HAS SHOWN AGITATED CUMULUS ALONG THE FRONT OVER THE PAST FEW HOURS. LOW-LEVEL CONVERGENCE ALONG THE FRONT IS WEAK AND IS EXPECTED TO REMAIN SO...WITH A WEAK MESO HIGH JUST N OF IAH. HOWEVER...AS TEMPERATURES CONTINUE TO WARM...THE FRONT SHOULD PROVIDE ENOUGH LIFT TO INITIATE THUNDERSTORMS IN THE LATE AFTERNOON NEAR THE MEXICO BORDER REGION AND THEN NEWD WITH TIME. STRONG INSTABILITY WILL EXIST WITH MLCAPES OF 3000 TO 4000 J/KG...ALTHOUGH SHEAR THROUGHOUT THE LOW AND MOST OF THE MID-LEVELS IS FAIRLY WEAK. MODEST WLY FLOW FROM 500 MB AND ABOVE WILL SUPPORT STORM ORGANIZATION GIVEN THE HIGH CAPE VALUES. ISOLATED SUPERCELLS PRODUCING LARGE HAIL APPEARS TO BE THE MAIN SEVERE THREAT. ..GRAMS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...CRP...EWX... 29310086 29530088 29799967 30049797 30599653 30509541 29409480 28729560 27669772 27569961 WWWW From mcd at goshenarc.org Tue Apr 25 19:28:18 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 15:28:18 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 251925 SWOMCD SPC MCD 251925 VAZ000-WVZ000-TNZ000-KYZ000-OHZ000-252130- MESOSCALE DISCUSSION 0653 NWS STORM PREDICTION CENTER NORMAN OK 0225 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN KY...CNTRL/SRN WV...WRN VA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 251925Z - 252130Z TRENDS ARE BEING MONITORED. IT REMAINS UNCERTAIN WHETHER INTENSIFICATION OF CONVECTIVE DEVELOPMENT...WHICH IS STILL EXPECTED...WILL BECOME SUFFICIENT TO WARRANT A WW. AREA OF STRONGER FORCING ASSOCIATED WITH MID-LEVEL IMPULSE CONTINUES TO SHIFT TOWARD THE CENTRAL APPALACHIANS. LATEST RUC MODEL SUGGESTS THIS FEATURE MAY BE CONTRIBUTING TO STRENGTHENING WESTERLY LOWER/MID TROPOSPHERIC FLOW ACROSS KENTUCKY/TENNESSEE...JUST SOUTH OF STRONGER CONFLUENT MID-LEVEL REGIME ACROSS THE UPPER OHIO VALLEY. LACK OF MORE SUBSTANTIAL DESTABILIZATION DUE TO RATHER WEAK MID-LEVEL LAPSE RATES APPEARS TO BE PRIMARY LIMITING FACTOR TO MORE VIGOROUS CONVECTIVE DEVELOPMENT...AND THIS MAY REMAIN THE CASE. HOWEVER...CAPE OF 500 TO 1000 J/KG IN MOIST MIXED BOUNDARY LAYER ACROSS CENTRAL/EASTERN KENTUCKY PROBABLY WILL STILL BE SUPPORTIVE OF AT LEAST SOME INTENSIFICATION TO ONGOING ACTIVITY. AND...A MORE ORGANIZED CLUSTER COULD SLOWLY EVOLVE IN 40+ KT MEAN FLOW LATE THIS AFTERNOON. IF THIS OCCURS...AT LEAST A RISK FOR SPORADIC DAMAGING WIND GUSTS SHOULD INCREASE BY THE 21-23Z TIME FRAME ACROSS WEST VIRGINIA...WHERE DRIER BUT DEEPLY MIXED BOUNDARY LAYER MAY ENHANCE EVAPORATIVE COOLING IN DOWNDRAFTS. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LWX...RNK...RLX...MRX...JKL...OHX... 38498313 38548273 38728188 39128048 38487975 38017971 37108027 36528188 36288303 36158406 36528482 37408384 37948348 WWWW From mcd at goshenarc.org Tue Apr 25 20:14:20 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 16:14:20 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252011 SWOMCD SPC MCD 252011 TNZ000-KYZ000-ILZ000-MOZ000-ARZ000-252115- MESOSCALE DISCUSSION 0654 NWS STORM PREDICTION CENTER NORMAN OK 0311 PM CDT TUE APR 25 2006 AREAS AFFECTED...SRN MO...NRN AR..PARTS OF WRN KY/TN CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252011Z - 252115Z A WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN INCREASING SEVERE THREAT. MID-LEVEL COOLING/FORCING FOR UPWARD VERTICAL MOTION...ASSOCIATED WITH UPPER TROUGH SHIFTING EAST OF THE CENTRAL PLAINS...APPEARS TO BE PRIMARY CONTRIBUTOR TO RECENT CONVECTIVE DEVELOPMENT ACROSS SOUTHWEST MISSOURI. THIS ACTIVITY APPEARS ROOTED IN LINGERING MOIST LAYER ABOVE FRONTAL INVERSION...BUT EASTWARD DEVELOPMENT IN CLOSER PROXIMITY TO SURFACE FRONT ALONG THE EASTERN ARKANSAS/MISSOURI BORDER AREA SEEMS POSSIBLE BY 21-22Z. LOW-LEVEL FLOW ACROSS THIS AREA IS GENERALLY WEAKENING...BUT 50+ KT 500 MB JET STREAK IS CONTRIBUTING TO FAVORABLE DEEP LAYER SHEAR FOR UPDRAFT ROTATION. ISOLATED CONVECTIVE DEVELOPMENT COULD EVOLVE INTO A CONVECTIVE CLUSTER...BUT BOUNDARY LAYER DESTABILIZATION OF ANY SIGNIFICANCE IN WAKE OF OVERNIGHT MESOSCALE CONVECTIVE SYSTEM MAY BE CONFINED TO A RELATIVELY NARROW PRE-FRONTAL CORRIDOR. ..KERR.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...PAH...MEG...LZK...SGF... 36809202 36849127 36989060 37239021 37268948 37008893 36388906 36028950 35859012 35819083 35969192 36179217 WWWW From mcd at goshenarc.org Tue Apr 25 20:56:22 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 16:56:22 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252052 SWOMCD SPC MCD 252052 TXZ000-252245- MESOSCALE DISCUSSION 0655 NWS STORM PREDICTION CENTER NORMAN OK 0352 PM CDT TUE APR 25 2006 AREAS AFFECTED...N-CNTRL/NERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252052Z - 252245Z SCATTERED ELEVATED THUNDERSTORMS ARE EXPECTED TO CONTINUE ALONG MID-LEVEL COLD FRONT...WITH MARGINALLY SEVERE HAIL THE MAIN THREAT. A WW IS NOT ANTICIPATED GIVEN MARGINAL AND FAIRLY ISOLATED NATURE OF THREAT. ELEVATED THUNDERSTORMS HAVE DEVELOPED ACROSS PORTIONS OF N-CNTRL TX AHEAD OF A 700 MB COLD FRONT. RUC SOUNDINGS INDICATE MOST UNSTABLE PARCELS NEAR THIS LEVEL POSSESSING CAPES OF AROUND 500 TO 750 J/KG. EFFECTIVE SHEAR IS MODEST /AROUND 30 TO 40 KTS/. THIS WILL SUPPORT ORGANIZED UPDRAFTS WHICH WILL PRODUCE HAIL...SOME OF WHICH COULD BE MARGINALLY SEVERE. QPF SIGNAL FROM 09Z SREF INDICATES ACTIVITY SHOULD PERSIST AND SPREAD EWD INTO PORTIONS OF NERN TX INTO THE EVENING. ..GRAMS.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...FWD...SJT... 31200114 31650059 32369939 32759848 33259733 33589602 33319552 32829538 32169547 31679618 31339730 31049876 30859989 30930063 WWWW From mcd at goshenarc.org Tue Apr 25 22:19:12 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 18:19:12 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 252216 SWOMCD SPC MCD 252216 VAZ000-NCZ000-TNZ000-252345- MESOSCALE DISCUSSION 0656 NWS STORM PREDICTION CENTER NORMAN OK 0516 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TN...SWRN VA...WRN NC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 252216Z - 252345Z THE CHANCE FOR ORGANIZED TSTMS APPEARS TO BE INCREASING ACROSS THE CNTRL APPALACHIANS AND INTO PORTIONS OF SWRN VA AND WRN NC THIS EVENING. A WATCH MAY BE NEEDED OVER PARTS OF THE REGION SHORTLY. SURFACE COLD FRONT WAS SAGGING SWD/SEWD TOWARD SWRN VA AND NERN TN WITH STORMS AHEAD OF THIS BOUNDARY INCREASING. LIFT ACROSS THE REGION WAS BEING FURTHER ENHANCED BY DIFFLUENT MID LEVEL FLOW AHEAD OF PROGRESSIVE AND LOW-AMPLITUDE SHORT WAVE TROUGH APPROACHING FROM KY/TN. THIS IMPULSE IS FORECAST TO INDUCE SURFACE WAVE DEVELOPMENT NEAR THE FRONT AS IT MOVES INTO VA LATER TONIGHT. DIURNAL HEATING HAS CONTRIBUTED TO LARGE TEMPERATURE-DEWPOINT SPREADS...AND THE DEVELOPMENT OF STEEP LOW TO MID LEVEL LAPSE RATES. AS CONVECTION INCREASES AHEAD OF THE FRONT AND NEAR THE DEVELOPING WAVE MOVING ACROSS THE REGION TONIGHT... PRIMARY THREAT APPEARS TO BE FROM A FEW STRONG TO DAMAGING WIND GUSTS WITH STORMS ORGANIZED INTO LINES OR CLUSTERS. AREAL COVERAGE MAY REMAIN LIMITED GIVEN TIME OF DAY...BUT FAVORABLE LARGE SCALE FORCING MAY SUSTAIN THE SEVERE THREAT INTO THE NIGHT. ..CARBIN.. 04/25/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...RAH...RNK...GSP...MRX... 36517883 35588023 35308204 35328309 35408372 35658392 36368299 36828185 37298043 37447995 37497933 37397896 36867861 WWWW From mcd at goshenarc.org Wed Apr 26 00:23:37 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 20:23:37 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260020 SWOMCD SPC MCD 260020 ALZ000-KYZ000-TNZ000-ILZ000-MOZ000-ARZ000-MSZ000-260115- MESOSCALE DISCUSSION 0657 NWS STORM PREDICTION CENTER NORMAN OK 0720 PM CDT TUE APR 25 2006 AREAS AFFECTED...SERN MO...SRN IL...WRN KY/TN...NERN AR CONCERNING...SEVERE THUNDERSTORM WATCH 250... VALID 260020Z - 260115Z A FEW SEVERE STORMS WITH LARGE HAIL AND POTENTIALLY DAMAGING WINDS WILL SPREAD EAST ACROSS EXTREME NERN AR AND PARTS OF WRN TN OVER THE NEXT HOUR. MOST INTENSE LONG-LIVED SUPERCELL HAS MOVED ACROSS THE MO BOOTHEEL LAST HOUR WITH A REPORT OF SIGNIFICANT HAIL TO 4 INCHES IN DIAMETER. THIS CELL...WHICH WAS NEAR DEVELOPING FRONTAL WAVE/LOW WILL CONTINUE MOVING ACROSS DYER COUNTY TN OVER THE NEXT 45 MINUTES BEFORE MOVING INTO GIBSON AND NRN CROCKETT COUNTIES THEREAFTER. ADDITIONAL CELLS WERE INCREASING AHEAD OF THE COLD FRONT IN NERN AR. STRONG LARGE SCALE FORCING ACROSS THE WARM SECTOR FROM DIFFLUENT MID LEVEL JET STREAK...AND VERY STEEP RATES EVIDENT IN LATEST LITTLE ROCK RAOB...WERE LIKELY CONTRIBUTING TO THE INCREASE IN THIS ACTIVITY. POTENTIAL FOR LARGE HAIL...AND POSSIBLY WINDS TO AROUND 50KT...COULD INCREASE ACROSS MISSISSIPPI COUNTY AR IN ABOUT AN HOUR. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...HUN...PAH...MEG...LSX...LZK...SGF... 37069121 36499122 36509252 35719239 35679290 35479288 35339199 35039204 34919058 35019013 35008793 35848798 35938811 36628802 36638768 36968764 37068797 37268817 37448788 37548796 37388877 37218864 37378953 37068998 37329007 37279063 WWWW From mcd at goshenarc.org Wed Apr 26 00:34:58 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 20:34:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260032 SWOMCD SPC MCD 260031 TXZ000-260200- MESOSCALE DISCUSSION 0658 NWS STORM PREDICTION CENTER NORMAN OK 0731 PM CDT TUE APR 25 2006 AREAS AFFECTED...S-CNTRL/SERN TX CONCERNING...SEVERE THUNDERSTORM WATCH 249... VALID 260031Z - 260200Z SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL WILL CONTINUE ACROSS SWRN PORTION OF WATCH. ADDITIONAL DEVELOPMENT IS LIKELY FURTHER NEWD IN THE NEXT FEW HOURS. CONTINUE WW. AN UNSTABLE ENVIRONMENT EXISTS ACROSS PORTIONS OF S-CNTRL TX WITH MLCAPES OF 2500 TO 3500 J/KG /PER 00Z CRP SOUNDING/. SUPERCELLS WILL CONTINUE TO THRIVE FOR THE NEXT FEW HOURS FROM AROUND KARNES TO JIM WELLS COUNTIES. ADDITIONAL DEVELOPMENT TO THE W OF THESE AREAS SUGGESTS A TRANSITION TO A MORE MULTICELLULAR MODE MAY OCCUR AFTER DARK. IMPRESSIVE SWD MOVING SUPERCELL ACROSS SRN DUVAL COUNTY WOULD APPEAR TO HAVE SOME TORNADIC POTENTIAL GIVEN MOVEMENT. HOWEVER...A VERY WEAK LOW-LEVEL WIND FIELD PER 00Z CRP SOUNDING AND INCREASING BOUNDARY LAYER STABILIZATION WILL TEND TO MITIGATE THIS THREAT. FURTHER NE...TIMING OF CONVECTIVE DEVELOPMENT IS STILL UNCERTAIN. 00Z LCH SOUNDING AND MODIFIED RUC SOUNDINGS SUGGEST THE AREA IS UNCAPPED. CELLS ARE BEGINNING TO INITIATE IN LAVACA COUNTY AND ADDITIONAL DOWNSTREAM DEVELOPMENT APPEARS LIKELY WITHIN THE NEXT FEW HOURS. 18Z NAM-WRF GUIDANCE INDICATED THE LOW-LEVEL MOISTURE CONVERGENCE ALONG THE COLD FRONT WILL STRENGTHEN BETWEEN 00 AND 03Z. THE ENVIRONMENT IS UNSTABLE WITH AROUND 2500 J/KG MLCAPE PER 00Z LCH SOUNDING. ALTHOUGH SHEAR IS RATHER WEAK...THE DEGREE OF INSTABILITY WILL SUPPORT A LARGE HAIL THREAT. ..GRAMS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...HGX...CRP...EWX...BRO... 28290026 28990041 29069958 29029872 29359756 30219652 31139492 30349466 29699439 29339433 28669530 27639721 27309783 27289887 27289932 WWWW From mcd at goshenarc.org Wed Apr 26 01:48:32 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 21:48:32 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260145 SWOMCD SPC MCD 260145 ARZ000-LAZ000-TXZ000-260315- MESOSCALE DISCUSSION 0659 NWS STORM PREDICTION CENTER NORMAN OK 0845 PM CDT TUE APR 25 2006 AREAS AFFECTED...EXTREME SRN AR...WRN LA...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 260145Z - 260315Z CHANCES FOR STRONG TO SEVERE TSTM DEVELOPMENT MAY BE INCREASING ACROSS PORTIONS OF NERN TX...WRN LA...AND POSSIBLY EXTREME SRN AR...LATE THIS EVENING. THESE AREAS ARE BEING MONITORED FOR A POSSIBLE SEVERE TSTM WATCH. PERSISTENT CLUSTER OF ELEVATED...BUT INTENSE...CONVECTION MOVING EAST ACROSS PARTS OF EAST TX APPEARS TO BE IN RESPONSE TO WEAK MID LEVEL IMPULSE ACTING ON VERY UNSTABLE CONDITIONS ABOVE SURFACE-BASED FRONTAL INVERSION. FARTHER EAST...FROM TX/LA BORDER NWD/EWD ACROSS THE MS VALLEY...WARM SECTOR AIR MASS AHEAD OF THE COLD FRONT HAS BEEN GRADUALLY RECOVERING IN THE WAKE OF EARLIER MCS. LATEST RUC...GFS...AND ETAKF GUIDANCE ALL SUGGEST RENEWED DEEP CONVECTION SHOULD OCCUR ALONG THE FRONT THROUGH LATE TONIGHT...POSSIBLY EVOLVING INTO ANOTHER MCS THAT WOULD THEN DEVELOP EAST ACROSS THE LOWER MS VALLEY. THIS SCENARIO APPEARS PROBABLE BASED ON EVENING RAOB DATA FROM SHV AND LCH INDICATING LITTLE INHIBITION EXISTS WITHIN A VERY MOIST AND UNSTABLE ENVIRONMENT. DEEP LAYER WLY FLOW AND ADEQUATE SHEAR IS EXPECTED TO REMAIN SUPPORTIVE OF BOTH INITIAL CELL ROTATION...AND EVENTUALLY ACCELERATING COLD POOLS. THUS... INCREASINGLY POTENTIAL FOR BOTH LARGE HAIL AND DAMAGING WINDS SUGGESTS A WATCH MAY BE NEEDED OVER THE AREA IN ABOUT AN HOUR. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LZK...LCH...SHV... 30209348 30489444 31099454 32939370 33289327 33249212 31629214 WWWW From mcd at goshenarc.org Wed Apr 26 02:16:03 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 22:16:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260213 SWOMCD SPC MCD 260213 NCZ000-VAZ000-TNZ000-260415- MESOSCALE DISCUSSION 0660 NWS STORM PREDICTION CENTER NORMAN OK 0913 PM CDT TUE APR 25 2006 AREAS AFFECTED...NRN NC...SWRN/SRN VA CONCERNING...SEVERE THUNDERSTORM WATCH 251... VALID 260213Z - 260415Z STRONG AND ISOLATED SEVERE STORMS WILL CONTINUE TO MOVE ACROSS SRN VA THE NC PIEDMONT THROUGH MIDNIGHT. AS COLD FRONT REDEVELOPS EAST OF THE APPALACHIANS...STRONG LARGE SCALE ASCENT ASSOCIATED WITH AN APPROACHING MID/UPPER LEVEL IMPULSE WILL MAINTAIN TSTMS AHEAD OF THE FRONT. WARM AND RELATIVELY DRY BOUNDARY LAYER MAY RESULT IN A BRIEF DAMAGING WIND THREAT FROM LINES AND CLUSTERS OF TSTMS MOVING EAST LATE THIS EVENING. EARLIER GSO RAOB INDICATED STEEP BOUNDARY LAYER LAPSE RATES AND SUFFICIENT UNIDIRECTIONAL SHEAR TO MAINTAIN A SEVERE WIND AND MARGINAL HAIL THREAT FROM A FEW OF THE MORE ROBUST UPDRAFTS. HOWEVER...OVERALL SEVERE POTENTIAL SHOULD GRADUALLY DECREASE AS BOUNDARY LAYER COOLING INHIBITS STRONGER DOWNDRAFTS. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...GSP...MRX... 35168283 35688304 36478201 36748133 37008131 37637998 37587963 37737923 37607893 37737853 37557771 37327726 37027740 36897754 36697752 36517711 36117724 35847737 35677764 35837775 35747825 35547884 35428027 WWWW From mcd at goshenarc.org Wed Apr 26 02:41:03 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 22:41:03 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260238 SWOMCD SPC MCD 260238 TXZ000-260415- MESOSCALE DISCUSSION 0661 NWS STORM PREDICTION CENTER NORMAN OK 0938 PM CDT TUE APR 25 2006 AREAS AFFECTED...FAR SRN TX CONCERNING...SEVERE THUNDERSTORM WATCH 252... VALID 260238Z - 260415Z THREAT FOR SVR STORMS WILL LIKELY BE CONFINED TO AREAS ALONG THE LOWER RIO GRANDE RIVER VALLEY THROUGH THE NEXT FEW HRS WITH A MORE LIMITED THREAT ALONG THE IMMEDIATE FAR SOUTH TX COAST. GIVEN PRESENCE OF LARGE SCALE DIFFLUENT FLOW PATTERN ALOFT...CONVECTION WILL LIKELY CONTINUE WELL BEYOND WW 252 EXPIRATION TIME /04Z/. TRENDS WILL BE MONITORED...BUT A NEW WW IS NOT ANTICIPATED AFTER 04Z...ALTHOUGH LOCAL WFO EXTENSION OF WW 252 MAY OCCUR. 00Z BRO SOUNDINGS SHOWED A PRONOUNCED WARM LAYER CENTERED AROUND 850 MB...WITH TEMPERATURES 3-4 DEGREES WARMER IN THIS LAYER THAN ON THE 00Z CRP SOUNDING. RECENT RADAR TRENDS INDICATE THAT THIS LARGE AMT OF CINH WILL LIKELY KEEP THE ORGANIZED SVR THREAT WEST OF THE IMMEDIATE FAR SOUTH TX COAST. VERY HIGH INSTABILITY AND MODEST SHEAR WILL CONTINUE TO FAVOR SVR HAIL/WIND WITH THE STRONGEST STORMS OVER THE LOWER RIO GRANDE RIVER VALLEY AWAY FROM THE COAST. LOW LEVEL SHEAR HAS INCREASED RECENTLY PER THE BRO 88-D VWP DATA...AND THUS AN ISOLATED TORNADO THREAT WILL ALSO REMAIN POSSIBLE /ESPECIALLY WITH THE SUPERCELL STORM OVER ERN JIM HOGG AND WRN BROOKS COUNTIES/. ADDITIONAL SVR STORMS MAY CONTINUE TO DEVELOP ALONG THE SFC FRONT/OUTFLOW BOUNDARY INTERSECTION OVER THE NWRN 1/3RD OF WW 252 FOR THE NEXT SEVERAL HRS WHERE LOW LEVEL CONVERGENCE WILL BE MAXIMIZED. ..CROSBIE.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CRP...BRO... 25839955 27539957 27309685 25569686 WWWW From mcd at goshenarc.org Wed Apr 26 03:04:08 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Tue, 25 Apr 2006 23:04:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260301 SWOMCD SPC MCD 260301 ALZ000-TNZ000-MSZ000-ARZ000-260400- MESOSCALE DISCUSSION 0662 NWS STORM PREDICTION CENTER NORMAN OK 1001 PM CDT TUE APR 25 2006 AREAS AFFECTED...NERN AR...WRN TN CONCERNING...SEVERE THUNDERSTORM WATCH 250... VALID 260301Z - 260400Z AFTER EARLIER INTENSE ACTIVITY...TSTMS NOW APPEAR TO BE WEAKENING RAPIDLY ACROSS REMAINING PORTIONS OF WW 250. HOWEVER...OTHER STORMS WERE BEGINNING TO DEVELOP ALONG THE COLD FRONT...NOW MOVING INTO INSTABILITY AXIS ACROSS ERN AR. WHILE A FEW STRONG STORMS COULD ACCOMPANY THE FRONTAL PASSAGE THROUGH LATE TONIGHT...AN ADDITIONAL WATCH IS NOT CURRENTLY PLANNED IN THE REGION. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OHX...HUN...MEG... 34988915 34889041 35309045 35948963 35868812 34968800 WWWW From mcd at goshenarc.org Wed Apr 26 04:45:48 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 00:45:48 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260443 SWOMCD SPC MCD 260442 LAZ000-ARZ000-TXZ000-260545- MESOSCALE DISCUSSION 0663 NWS STORM PREDICTION CENTER NORMAN OK 1142 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TX...LA CONCERNING...SEVERE THUNDERSTORM WATCH 253... VALID 260442Z - 260545Z STORMS CONTINUE TO INCREASE ALONG COLD FRONT MOVING SLOWLY ACROSS LA AND THE UPPER TX COAST LATE TONIGHT. MOIST AND MARGINALLY UNSTABLE CONDITIONS IN POST-MCS AIR MASS ACROSS LA SHOULD CONTINUE TO SUPPORT MODEST/STRONG UPDRAFTS GIVEN PERSISTENT LIFT ALONG THE ADVANCING FRONTAL CIRCULATION. ADEQUATE DEEP SHEAR OF 30-45KT OBSERVED ON WINFIELD AND DE QUEEN WIND PROFILERS SUGGESTS THAT SUPERCELL STRUCTURE REMAINS A POSSIBILITY WITH THIS CONVECTION. A COUPLE OF HAIL/WIND EVENTS COULD OCCUR AS ACTIVITY DEVELOPS SLOWLY EAST TOWARD THE MS RIVER THROUGH THE NIGHT. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...JAN...LCH...SHV...HGX... 29219222 29379373 29089494 28939533 30199470 31929459 32459403 33069340 33049197 32209190 30769220 WWWW From mcd at goshenarc.org Wed Apr 26 05:00:11 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 01:00:11 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260457 SWOMCD SPC MCD 260457 TXZ000-260630- MESOSCALE DISCUSSION 0664 NWS STORM PREDICTION CENTER NORMAN OK 1157 PM CDT TUE APR 25 2006 AREAS AFFECTED...ERN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 260457Z - 260630Z MARGINAL SEVERE HAIL POTENTIAL MAY BE INCREASING ACROSS PORTIONS OF SERN/SCNTRL TX EARLY TODAY. PERSISTENT ISENTROPIC LIFT ATOP LOW LEVEL FRONTAL INVERSION IS APPARENTLY ADEQUATE FOR PARCELS TO AGAIN REACH AN LFC ABOVE 850MB ACROSS SERN/SCNTRL TX LATE TONIGHT. BAND OF ELEVATED STORMS WAS NOW INCREASING ALONG THE ELEVATED FRONTAL SURFACE...GENERALLY ALONG A LINE FROM HDO TO AUS TO CLL. LATEST RUC SOUNDINGS FROM THE REGION INDICATED MUCAPE OF AROUND 1000 J/KG AVAILABLE TO THIS NEW ROUND OF STORMS. STRONG CLOUD BEARING SHEAR OF 40-60KT FURTHER SUPPORTS UPDRAFT INTENSIFICATION AND PERSISTENCE. UNCERTAINTY EXISTS REGARDING LARGE SCALE SUPPORT FOR STRONGER UPWARD MOTION ACROSS THE REGION...AND EXTENT OF SEVERE STORM COVERAGE. ADDITIONALLY...WITH SEVERE THREAT LIKELY CONFINED TO MARGINALLY SEVERE HAIL OF ABOUT AN INCH OR SO...CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED. ..CARBIN.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...HGX...FWD...EWX... 30339555 29379839 29489955 30259884 31159636 31389544 31229523 WWWW From mcd at goshenarc.org Wed Apr 26 06:26:41 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 02:26:41 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260624 SWOMCD SPC MCD 260623 ALZ000-MSZ000-LAZ000-ARZ000-260830- MESOSCALE DISCUSSION 0665 NWS STORM PREDICTION CENTER NORMAN OK 0123 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS ERN LA...NRN AL...MUCH OF MS. CONCERNING...CONVECTIVE TRENDS VALID 260623Z - 260830Z GEN TSTM POTENTIAL WILL INCREASE ACROSS CORRIDOR FROM NRN AL TO SWRN MS THROUGH AT LEAST 9Z. MOST OF THIS ACTIVITY SHOULD REMAIN BELOW SEVERE LIMITS...HOWEVER OCCASIONAL DAMAGING GUSTS AND MRGLLY SEVERE HAIL ARE POSSIBLE. WW NOT ANTICIPATED ATTM. CONVECTION ACROSS THIS REGION WILL OCCUR IN ASSOCIATION WITH LOOSELY ORGANIZED TSTM COMPLEXES NOW MOVING ESEWD FROM SWRN TN AND NWRN MS TOWARD N-CENTRAL AL...AS WELL AS MOVING EWD FROM WW 253 ACROSS MS RIVER FROM ERN LA INTO WRN MS. ADDITIONAL DEVELOPMENT ALSO IS POSSIBLE ACROSS THIS REGION. SFC MESOANALYSIS SHOWS OUTFLOW BOUNDARY FROM EARLIER MCS FROM FL PANHANDLE INTO NRN GULF...THEN NWWD ACROSS EXTREME SE TX AND EXTREME SWRN LA. NRN PORTION OF MCS-OVERTURNED AIR ALOFT APPEARS TO LIE NEAR BHM-GWO LINE. MODIFIED RAOBS AND RUC SOUNDINGS INDICATE ELEVATED MUCAPES AROUND 500 J/KG ACROSS PORTIONS CENTRAL/SRN MS...TRENDING UPWARD TO 1500-2000 J/KG RANGE WITH NRN EXTENT INTO NRN PORTIONS MS/AL WHERE EARLIER MCS DID NOT AFFECT AIR MASS ALOFT AS MUCH. GIVEN STEEPER LAPSE RATES OVER NRN PORTIONS MS/AL...AND SOMEWHAT LARGER EFFECTIVE SHEAR PROFILES WITH NRN EXTENT...HAIL POTENTIAL WILL BE LARGER WITH ACTIVITY IN THOSE AREAS THAN WITH COMPLEX MOVING EWD FROM LA. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BMX...HUN...MEG...JAN...LIX...LCH...SHV... 30789212 32159205 33189157 34479009 34958867 35008789 34818642 34218633 33908677 33728787 33028895 31488921 30469129 30359214 WWWW From mcd at goshenarc.org Wed Apr 26 08:14:42 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:14:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260811 SWOMCD SPC MCD 260811 LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0311 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SW TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260811Z - 260945Z THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650 WWWW From mcd at goshenarc.org Wed Apr 26 08:22:50 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:22:50 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260820 SWOMCD SPC MCD 260819 COR LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0319 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260819Z - 260945Z CORRECTED FOR TYPO THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650 WWWW From mcd at goshenarc.org Wed Apr 26 08:22:56 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:22:56 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260811 SWOMCD SPC MCD 260811 LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0311 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SW TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260811Z - 260945Z THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650  From mcd at goshenarc.org Wed Apr 26 08:26:06 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 04:26:06 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 260820 SWOMCD SPC MCD 260819 COR LAZ000-TXZ000-260945- MESOSCALE DISCUSSION 0666 NWS STORM PREDICTION CENTER NORMAN OK 0319 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX...CENTRAL/SRN LA. CONCERNING...SEVERE THUNDERSTORM WATCH 253...254... VALID 260819Z - 260945Z CORRECTED FOR TYPO THREAT FOR ELEVATED SEVERE TSTM DEVELOPMENT PERSISTS BEHIND SFC COLD FRONT ACROSS MOST OF SE TX...IN AREA OF FAVORABLE BUOYANCY AND SHEAR ALOFT THAT IS ROOTED ATOP FRONTAL SFC. TSTMS N HOU HAVE PRODUCED HAIL UP TO 2 INCHES DIAMETER WITHIN PAST 1-2 HOURS. MORE LARGE HAIL IS EXPECTED FROM MOST VIGOROUS TSTMS IN LARGE AREA OF CONVECTION COVERING MUCH OF TX/LA S OF A LINE FROM 60 WNW HOU...LFK...POE. ADDITIONAL DEVELOPMENT IS POSSIBLE FARTHER W AND SW ACROSS WW...ALSO N OF SFC COLD FRONT. MODIFIED RUC SOUNDINGS INDICATE STEEP MIDLEVEL LAPSE RATES PERSIST ACROSS THIS AREA...WITH BROAD PLUME OF MOIST ASCENT ATOP STABLE FRONTAL LAYER. ELEVATED MUCAPES 1500-2500 J/KG ARE COMMON IN AREAS NOT STABILIZED BY RECENT CONVECTION. DEEP-LAYER SHEAR THROUGH BUOYANT LAYER STRENGTHENS WITH SWWD EXTENT ALONG MID/UPPER TX COASTAL PLAIN...RANGING FROM APPROXIMATELY 35 KT AROUND HOU TO OVER 60 KT NEAR VCT. THIS INDICATES POTENTIAL FOR ANY NEW DEVELOPMENT OVER TX COASTAL PLAIN TO ROTATE AND PRODUCE LARGE/DAMAGING HAIL. PORTIONS SWRN/S-CENTRAL LA NOW UNDER WW 253 EWD ACROSS PORTIONS S-CENTRAL/SERN LA WILL BE MONITORED FOR ADDITIONAL WW. BESIDES MCS SPREADING ACROSS SRN PORTION WW 253...ISOLATED SUPERCELL HAS DEVELOPED AND INTENSIFIED QUICKLY OVER TERREBONNE COUNTY ALONG BOUNDARY BETWEEN OUTFLOW-OVERTURNED AIR INLAND...AND MARINE AIR MASS ADVECTING INLAND FROM GULF. LOW LEVEL SHEAR ENHANCEMENTS ASSOCIATED WITH MARINE BOUNDARY WITHIN ABOUT 50 NM OF COAST SUPPORT SUPERCELL POTENTIAL DESPITE MRGL MIDLEVEL WINDS. LOW 70S F SFC DEW POINTS ALONG/S OF THAT BOUNDARY CONTRIBUTE TO SFC-BASED BUOYANCY WITH MLCAPES 2000-3000 J/KG. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LIX...LCH...SHV...HGX...CRP...EWX... 28859756 29399772 29979760 30359692 31399475 31469237 29829039 29279019 29089054 29459212 28989514 28639650  From mcd at goshenarc.org Wed Apr 26 11:08:57 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 07:08:57 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261106 SWOMCD SPC MCD 261105 TXZ000-261200- MESOSCALE DISCUSSION 0667 NWS STORM PREDICTION CENTER NORMAN OK 0605 AM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS SE TX. CONCERNING...SEVERE THUNDERSTORM WATCH 254... VALID 261105Z - 261200Z SEVERE TSTM POTENTIAL IS DIMINISHING ACROSS WW AREA. SOME OR ALL OF WW MAY BE CANCELLED BEFORE SCHEDULED 12Z EXPIRATION...OTHERWISE WW WILL BE ALLOWED TO EXPIRE WITHOUT FURTHER ISSUANCE. VWP/PROFILER DATA INDICATES SUBTLE MIDLEVEL SHORTWAVE TROUGH AND SPEED MAX CLOSELY CORRESPONDS TO WRN EDGE OF MOST CONCENTRATED PRECIP...AND IS APCHG SABINE RIVER ATTM. MEANWHILE...STABLE/POST-FRONTAL BOUNDARY LAYER CONTINUES TO DEEPEN ACROSS REGION. MAJORITY OF CONVECTION HAS MOVED/DEVELOPED EWD ACROSS LA...OUT OF AREA OF OPTIMAL COMBINED INSTABILITY/SHEAR PROFILES THAT STILL LINGER OVER PORTIONS S TX...BASED ON MODIFIED RAOBS AND RUC SOUNDINGS. ELEVATED BUOYANCY REMAINS FAVORABLE OVER REGION...AND EFFECTIVE SHEAR GENERALLY STRENGTHENS WITH WWD EXTENT. OCCASIONAL TSTM FORMATION AND POTENTIAL FOR MRGLLY SEVERE HAIL MAY LINGER WELL N OF FRONT...GENERALLY E OF I-45 AND NEAR NRN EDGE OF ORIGINAL WW. HOWEVER...APPARENT LACK OF ELEVATED ASCENT BEHIND MIDLEVEL PERTURBATION INDICATES LOW PROBABILITY FOR ADDITIONAL/ORGANIZED DEVELOPMENT BEFORE WW EXPIRES. ..EDWARDS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LCH...SHV...HGX... 30889623 30919564 31369494 30749461 29869436 29859493 30099510 30019530 30099550 30079581 30209584 30219612 30409610 WWWW From mcd at goshenarc.org Wed Apr 26 15:07:14 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 11:07:14 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261504 SWOMCD SPC MCD 261504 SCZ000-GAZ000-261630- MESOSCALE DISCUSSION 0668 NWS STORM PREDICTION CENTER NORMAN OK 1004 AM CDT WED APR 26 2006 AREAS AFFECTED...NERN GA INTO WRN SC CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261504Z - 261630Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT. A WW LIKELY WILL BE NEEDED IN THE LEE OF THE SOUTHERN APPALACHIANS... PERHAPS BY EARLY AFTERNOON. INITIATION OF NEW CONVECTIVE DEVELOPMENT IS ALREADY UNDERWAY ACROSS THE HIGHER TERRAIN OF WESTERN SOUTH CAROLINA. THIS IS PROBABLY LARGELY DRIVEN BY OROGRAPHIC FORCING...BUT STRENGTHENING DIVERGENCE ALOFT...AHEAD OF SHORT WAVE TROUGH DIGGING FROM THE MIDDLE MISSISSIPPI VALLEY INTO THE TENNESSEE VALLEY...WILL COME OF INCREASING INFLUENCE THROUGH MID DAY. STORMS ARE EXPECTED TO INCREASE IN COVERAGE TO THE LEE OF THE APPALACHIANS THROUGH 16-18Z...ACROSS MUCH OF NORTHEAST GEORGIA INTO WESTERN SOUTH CAROLINA...WHERE MOIST BOUNDARY LAYER WILL CONTINUE TO DESTABILIZE WITH INSOLATION. MOST UNSTABLE CAPE IS ALREADY IN EXCESS OF 1500 J/KG...IN FAVORABLY SHEARED REGIME BENEATH 40+ KT WESTERLY MID-LEVEL FLOW...WHICH SHOULD BE SUFFICIENT FOR AT LEAST BRIEF MID-LEVEL UPDRAFT ROTATION. LARGE HAIL IS EXPECTED TO BE PRIMARY SEVERE THREAT THOUGH EARLY AFTERNOON...BEFORE DAMAGING WIND POTENTIAL INCREASES TO THE EAST SOUTHEAST LATER ON. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CAE...GSP...FFC... 34428359 34598298 35058181 34748066 34018069 33238239 33338323 33888408 34198424 WWWW From mcd at goshenarc.org Wed Apr 26 16:05:49 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 12:05:49 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261602 SWOMCD SPC MCD 261602 GAZ000-FLZ000-261730- MESOSCALE DISCUSSION 0669 NWS STORM PREDICTION CENTER NORMAN OK 1102 AM CDT WED APR 26 2006 AREAS AFFECTED...NRN FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261602Z - 261730Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT AND POSSIBILITY OF A WW. COLD POOL ASSOCIATED WITH MESOSCALE CONVECTIVE SYSTEM HAS OVERSPREAD MUCH OF SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI INTO THE WESTERN FLORIDA PANHANDLE...WITH STRONGEST PORTION SURGING SOUTHEAST OF THE LOUISIANA COAST. HOWEVER...MORE VIGOROUS CLUSTER OF STORMS ...NOW DEVELOPING EAST OF MOBILE...REMAINS IN CLOSE PROXIMITY TO COASTAL AREAS...AND APPEARS SUPPORTED BY FORCING ASSOCIATED WITH IMPULSE EMBEDDED WITHIN STRONGER MID/UPPER STREAM OF FLOW ALONG GULF COASTAL AREAS. MODELS SUGGEST THIS FORCING WILL GRADUALLY SHIFT EAST THROUGH THE FLORIDA BIG BEND REGION BY THE 20-21Z TIME FRAME. SURFACE DEW POINTS ACROSS THE FLORIDA BIG BEND/EASTERN PANHANDLE... INCLUDING THE TALLAHASSEE AREA...TO THE SOUTH OF AN OLD CONVECTIVE BOUNDARY WHICH EXTENDS THROUGH THE VALDOSTA/SAVANNAH GEORGIA AREAS ...ARE AROUND 70F. THIS IS CONTRIBUTING TO MIXED LAYER CAPE OF 1000 TO 2000 WITH INSOLATION...WHICH SEEMS LIKELY TO MAINTAIN VIGOROUS CONVECTIVE DEVELOPMENT INTO AND THROUGH THE AFTERNOON HOURS. HIGH PRECIPITABLE WATER CONTENT AIR /AROUND 2 INCHES/ FEEDING INTO CONVECTION WILL SUPPORT VERY HEAVY RAINFALL...BUT LOW HUMIDITIES AT MID LEVELS WILL ENHANCE EVAPORATIVE COOLING IN DOWNDRAFTS...AND ADDITIONAL SIGNIFICANT COLD POOLS APPEAR POSSIBLE. MODELS SUGGEST THAT A WESTERLY LOW-LEVEL JET WILL STRENGTHEN ACROSS NORTHERN FLORIDA WITH APPROACH OF UPPER IMPULSE. AS THIS OCCURS...FORWARD PROPAGATION OF ANY COLD POOLS WILL BE ENHANCED...ALONG WITH RISK OF DAMAGING WINDS. THIS SEEMS POSSIBLE NEAR/EAST OF TALLAHASSEE THROUGH THE JACKSONVILLE AREAS DURING THE 18-21Z TIME FRAME. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...TBW...JAX...TAE... 31708067 30498072 30038121 29678215 29088320 28798544 29968549 30878492 31298410 31258269 31638168 31838116 WWWW From mcd at goshenarc.org Wed Apr 26 18:19:42 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 14:19:42 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261817 SWOMCD SPC MCD 261816 SCZ000-GAZ000-261945- MESOSCALE DISCUSSION 0670 NWS STORM PREDICTION CENTER NORMAN OK 0116 PM CDT WED APR 26 2006 AREAS AFFECTED...SOUTH CAROLINA AND PARTS OF EASTERN GEORGIA CONCERNING...SEVERE THUNDERSTORM WATCH 255... VALID 261816Z - 261945Z CONTINUE WW. SCATTERED INTENSE CONVECTIVE DEVELOPMENT IS ONGOING FROM THE LEE OF THE SOUTHERN APPALACHIANS INTO THE SOUTH CAROLINA PIEDMONT. THIS IS GENERALLY ALONG/SOUTH OF SURFACE FRONTAL ZONE EXTENDING FROM UPSTATE SOUTH CAROLINA THROUGH AREAS NEAR/NORTH OF COLUMBIA INTO THE VICINITY OF MYRTLE BEACH. WEAK SURFACE LOW NEAR COLUMBIA IS PROVIDING A FOCUS FOR STRONGER LOW-LEVEL CONVERGENCE...AND CONSOLIDATION OF ACTIVITY INTO A MORE SUBSTANTIAL CONVECTIVE CLUSTER APPEARS POSSIBLE ACROSS THE CENTRAL SOUTH CAROLINA PIEDMONT THROUGH 21Z. OBJECTIVE ANALYSIS INDICATES MIXED LAYER CAPE IN WARM SECTOR OF LOW IS ON THE ORDER OF 2000 J/KG. AS CONVECTION BEGINS TO INGEST THIS AIR MASS...INTENSIFYING UPDRAFTS IN SUFFICIENTLY SHEARED ENVIRONMENT FOR SUPERCELLS COULD BECOME SUPPORTIVE OF ISOLATED VERY LARGE HAIL NEAR COLUMBIA. THROUGH LOW-LEVEL HODOGRAPHS ARE GENERALLY SMALL/WEAK...AN ISOLATED TORNADO IS POSSIBLE...BEFORE DAMAGING WIND THREAT INCREASES TOWARD THE COASTAL PLAIN LATER THIS AFTERNOON. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...ILM...CHS...CAE...GSP... 34098097 34238061 33737979 33527977 33008017 33168082 33258133 33238174 33888237 34008182 WWWW From mcd at goshenarc.org Wed Apr 26 19:09:17 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 15:09:17 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261906 SWOMCD SPC MCD 261905 GAZ000-ALZ000-TNZ000-MSZ000-262100- MESOSCALE DISCUSSION 0671 NWS STORM PREDICTION CENTER NORMAN OK 0205 PM CDT WED APR 26 2006 AREAS AFFECTED...PORTIONS OF ERN MS/MOST OF AL/FAR NW GA CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261905Z - 262100Z SCATTERED THUNDERSTORM CLUSTERS WILL MOVE EWD FROM NRN AL TOWARDS WW 255. ADDITIONAL DEVELOPMENT MAY OCCUR FURTHER S ALONG COLD FRONT ACROSS ERN MS INTO CNTRL/SRN AL. MARGINAL LAPSE RATES AND OVERALL LACK OF INSTABILITY WILL LIMIT THE LARGE HAIL THREAT. A WW IS NOT ANTICIPATED. A SMALL AREA OF CLEARING BEHIND MORNING CONVECTION AND AHEAD OF SYNOPTIC COLD FRONT HAS LED TO SCATTERED THUNDERSTORM DEVELOPMENT ACROSS PORTIONS OF NRN AL. MODIFIED 12Z RAOBS AND RUC SOUNDINGS INDICATE A WEAKLY UNSTABLE ENVIRONMENT WITH MLCAPES OF 500 TO 800 J/KG. EFFECTIVE SHEAR AROUND 40 KTS WOULD SUPPORT UPDRAFT ORGANIZATION. HOWEVER...MARGINAL MID-LEVEL LAPSE RATES WILL LIKELY LIMIT THE LARGE HAIL THREAT. FURTHER S INTO PORTIONS OF ERN MS AND CNTRL/SRN AL...ADDITIONAL DESTABILIZATION WILL TAKE PLACE IN THE NEAR TERM WITH CONVECTIVE DEBRIS FROM GULF COAST MCS MOVING E OF AREA. THIS SHOULD ALLOW MLCAPES TO REACH AROUND 500 J/KG. WITH APPROACH OF THE COLD FRONT...CONVECTIVE DEVELOPMENT MAY OCCUR. HOWEVER...THE LINGERING EFFECTS OF THE MORNING MCS WILL KEEP MARGINAL MID-LEVEL LAPSE RATES INTACT AND MITIGATE THE LARGE HAIL THREAT. ..GRAMS.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...MRX...FFC...BMX...HUN...MOB...JAN... 31718980 33208837 34298703 35018590 34908455 34218453 33368504 32068634 31188744 31238901 WWWW From mcd at goshenarc.org Wed Apr 26 19:41:58 2006 From: mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Wed, 26 Apr 2006 15:41:58 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 261938 SWOMCD SPC MCD 261938 GAZ000-FLZ000-262115- MESOSCALE DISCUSSION 0672 NWS STORM PREDICTION CENTER NORMAN OK 0238 PM CDT WED APR 26 2006 AREAS AFFECTED...SW GA...NE FL CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 261938Z - 262115Z SEVERE THREAT SOUTH OF WW 255 SEEMS LIKELY TO REMAIN ISOLATED... LIMITED TO AREAS SOUTHWEST THROUGH SOUTH OF JACKSONVILLE. AN ADDITIONAL WW IS NOT CURRENTLY ANTICIPATED...BUT TRENDS ARE BEING MONITORED. LATEST RUC SUGGESTS 30 TO 35 KT SOUTHWESTERLY LOW-LEVEL JET MAY BE DEVELOPING ACROSS THE FLORIDA BIG BEND THROUGH SOUTHERN GEORGIA... MUCH AS EARLIER PROGGED BY NAM/GFS. THIS SEEMS TO BE ENHANCING EASTWARD PROPAGATION OF CONVECTIVELY GENERATED SURFACE COLD POOL WHICH IS PROGRESSING EAST OF THE ALBANY/VALDOSTA/TALLAHASSEE AREAS. DIVERGENT WEAK WESTERLY SURFACE FLOW AHEAD OF COLD POOL IS LIMITING STRENGTH OF UPLIFT ALONG GUST FRONT...WHICH LIKELY WILL PRECLUDE EVOLUTION OF A LARGER CONVECTIVE CLUSTER. MOST SIGNIFICANT CONVECTION SEEMS LIKELY TO CONTINUE TO DEVELOP NORTH/EAST OF BRUNSWICK INTO THE SAVANNAH RIVER VALLEY. HOWEVER...ADDITIONAL NEW VIGOROUS THUNDERSTORM ACTIVITY STILL APPEARS POSSIBLE...AS GUST FRONT PROGRESSES INTO AREAS SOUTHWEST THROUGH SOUTH OF JACKSONVILLE. THIS IS WHERE LOW-LEVEL LAPSE RATES REMAIN STEEPEST...PROVIDING A FAVORABLE ENVIRONMENT FOR STRONG WIND GUSTS...PERHAPS SOME MARGINALLY SEVERE HAIL. ..KERR.. 04/26/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...CHS...TBW...JAX...TAE... 31678271 31808224 31798148 31068110 30348114 29648199 29228290 29098371 29148439 29798411 30218335 WWWW From Mcd at goshenarc.org Fri Apr 28 12:03:33 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 08:03:33 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281203 SWOMCD SPC MCD 281203 KSZ000-OKZ000-TXZ000-COZ000-NMZ000-281400- MESOSCALE DISCUSSION 0675 NWS STORM PREDICTION CENTER NORMAN OK 0703 AM CDT FRI APR 28 2006 AREAS AFFECTED...NERN NM ACROSS THE TX/OK PNHDLS...SWRN AND CNTRL KS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281203Z - 281400Z TSTMS ARE EXPECTED TO BECOME MORE NUMEROUS AND STRONGER IN THE NEXT FEW HOURS FROM NERN NM EWD AND NEWD ACROSS PORTIONS OF THE OK/TX PNHDLS...AND INTO KS. SOME OF THESE STORMS WILL LIKELY PRODUCE HAIL. WHILE IT DOES NOT APPEAR IMMINENT...A WATCH MIGHT BE NEEDED FOR SOME OF THESE AREAS THIS MORNING. ELEVATED CONVECTION WAS ON THE INCREASE FROM THE SRN HIGH PLAINS TO THE SCNTRL PLAINS THIS MORNING AS A PAIR OF UPPER LEVEL SHORT WAVE TROUGHS BEGIN TO IMPOSE STRONGER LARGE SCALE ASCENT OVER THE REGION. AS A NRN STREAM IMPULSE DIGS SEWD ACROSS CO...A STRONG SRN STREAM UPPER LOW WAS DEVELOPING EAST FROM THE AZ/NM BORDER. THE MID/UPPER LEVEL DIFFLUENT FLOW AHEAD OF THE SRN SYSTEM HAS ENHANCED THE NOCTURNAL LOW LEVEL JET AND AIDED MOISTURE TRANSPORT NWD INTO A SW-NE ORIENTED DEFORMATION AXIS SITUATED FROM NM NEWD ACROSS KS. CONTINUED STRENGTHENING OF UPWARD MOTION/DPVA ASSOCIATED WITH THE NRN STREAM TROUGH...AND LARGE SCALE UPPER JET COUPLING BETWEEN THE NRN AND SRN SYSTEMS...SHOULD MAINTAIN A FAVORABLE ENVIRONMENT FOR INCREASINGLY WIDESPREAD CONVECTION THROUGH THE MORNING. DESPITE RECENT UPWARD TREND IN STORM COVERAGE ACROSS KS AND PRESENCE OF MODEST LAPSE RATES OF 7-8 C/KM...EFFECTIVE SHEAR ACROSS PARTS OF THE AREA APPEARS SOMEWHAT LIMITED WITHIN DEVELOPING MID LEVEL DEFORMATION ZONE BETWEEN NRN AND SRN STREAM SYSTEMS. HOWEVER... STEEPER LAPSE RATES...STRONGER SHEAR AND FORCING ARE FORECAST TO OVERSPREAD NM...TX/OK PNHDLS...AND SWRN KS AREAS THROUGH THE MORNING. MORE INTENSE CONVECTION...POSSIBLY IN THE FORM OF A FEW ELEVATED SUPERCELLS WITH PERSISTENT STORM UPDRAFTS AND LARGE HAIL...COULD DEVELOP IN THESE AREAS. A SEVERE TSTM WATCH MAY BE NEEDED AS ACTIVITY DEVELOPS THROUGH THE MORNING. ..CARBIN.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TOP...ICT...OUN...GID...DDC...GLD...AMA...PUB...ABQ... 36349959 35100268 35460410 36460406 37170182 38820085 39589834 39259703 38369687 WWWW From Mcd at goshenarc.org Fri Apr 28 15:24:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 11:24:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281524 SWOMCD SPC MCD 281523 OKZ000-TXZ000-281700- MESOSCALE DISCUSSION 0676 NWS STORM PREDICTION CENTER NORMAN OK 1023 AM CDT FRI APR 28 2006 AREAS AFFECTED...ERN TX PNHDL...WRN OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281523Z - 281700Z TRENDS ARE BEING MONITORED FOR INCREASING SEVERE THREAT AND POSSIBILITY OF A WW. NEW CONVECTIVE DEVELOPMENT IS EXPECTED ACROSS THE EASTERN TEXAS PANHANDLE AND PARTS OF WESTERN OKLAHOMA THROUGH THE 17-19Z TIME FRAME. THIS SEEMS LIKELY TO OCCUR IN ASSOCIATION WITH STRONGER MID-LEVEL COOLING/ASCENT IN EXIT REGION OF 70+ KT CYCLONIC 500 MB JET STREAK...WHICH CONTINUES TO SLOWLY NOSE INTO SOUTHWEST TEXAS. MID-LEVEL LAPSE RATES ARE ALREADY RATHER STEEP AND...WITH FURTHER DESTABILIZATION...MOST UNSTABLE CAPE FOR MOIST PARCELS ABOVE LINGERING NEAR SURFACE INVERSION LAYER MAY APPROACH 2000 J/KG. SHEAR PROFILES IN CLOUD BEARING LAYER APPEAR SUPPORTIVE OF MID- LEVEL UPDRAFT ROTATION...WHICH SHOULD ENHANCE POTENTIAL FOR LARGE HAIL IN STRONGER STORMS. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...LUB...AMA... 35740108 36420043 36519957 35549887 33849909 33300064 34400082 35090117 WWWW From Mcd at goshenarc.org Fri Apr 28 15:44:10 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 11:44:10 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281543 SWOMCD SPC MCD 281543 TXZ000-281715- MESOSCALE DISCUSSION 0677 NWS STORM PREDICTION CENTER NORMAN OK 1043 AM CDT FRI APR 28 2006 AREAS AFFECTED...TEXAS SOUTH PLAINS CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281543Z - 281715Z A TORNADO WATCH WILL LIKELY BE NEEDED...POSSIBLY BEFORE NOON. TIMING OF INITIATION OF SURFACE-BASED CONVECTIVE DEVELOPMENT IS A BIT UNCERTAIN. HOWEVER..LATEST OBJECTIVE ANALYSIS SUGGESTS INHIBITION HAS BECOME RATHER WEAK NEAR/JUST AHEAD OF DRY LINE...FROM THE LUBBOCK AREA SOUTHWARD TO NEAR SAN ANGELO...WHERE MIXED LAYER CAPE IS ON THE ORDER OF 1500 J/KG. FURTHER DESTABILIZATION WILL OCCUR WITH CONTINUING INSOLATION...AND A GRADUAL MID-LEVEL COOLING AS MID/UPPER JET NOSES ACROSS WEST TEXAS. A 30+ KT SOUTHERLY LOW-LEVEL JET IS CONTRIBUTING TO SHEAR PROFILES EASILY SUFFICIENT FOR SUPERCELLS...WHICH COULD FORM AS EARLY AS 17-18Z. LATEST TRENDS IN SATELLITE IMAGERY SUGGEST THIS IS MOST LIKELY JUST TO THE SOUTHEAST OF LUBBOCK. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SJT...LUB...MAF... 33750182 33530079 32980042 32240067 31360115 31290199 32080193 32800219 WWWW From Mcd at goshenarc.org Fri Apr 28 18:04:52 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 14:04:52 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 281804 SWOMCD SPC MCD 281804 OKZ000-TXZ000-281930- MESOSCALE DISCUSSION 0679 NWS STORM PREDICTION CENTER NORMAN OK 0104 PM CDT FRI APR 28 2006 AREAS AFFECTED...N CNTRL TX THRU S CNTRL/SE OK CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 281804Z - 281930Z TRENDS ARE BEING MONITORED FOR THE POSSIBILITY OF AN ADDITIONAL WW EAST OF WW 256. WHILE SURFACE-BASED CONVECTIVE INITIATION APPEARS UNDERWAY ALONG DRY LINE...SOUTHEAST OF LUBBOCK THROUGH AREAS EAST/SOUTHEAST OF MIDLAND...AN INCREASE IN CONVECTIVE DEVELOPMENT IS ALSO ONGOING NORTH OF THE TEXAS HILL COUNTRY INTO AREAS NEAR/WEST OF DALLAS/FORT WORTH. THIS APPEARS BASED ABOVE AT LEAST SHALLOW NEAR SURFACE INVERSION LAYER...IN ASSOCIATION WITH BROADER AREA OF ISENTROPIC ASCENT... DOWNSTREAM OF SOUTHERN PLATEAU CLOSED LOW. THIS FORCING WILL SPREAD NORTHEASTWARD ACROSS THE RED RIVER VALLEY THROUGH THE 20-21Z TIME FRAME...AS UPPER SYSTEM SHIFTS INTO THE SOUTHERN ROCKIES. STEEP MID-LEVEL LAPSE RATES ARE CONTRIBUTING TO MOST UNSTABLE CAPE ON THE ORDER OF 1000 J/KG OVER A FAIRLY BROAD AREA OF THE SOUTHERN PLAINS. THIS WILL SUPPORT RISK OF LARGE HAIL IN STRONGEST CELLS...THOUGH INCREASINGLY WIDESPREAD NATURE OF CONVECTION MAY TEND TO MITIGATE THREAT MOST AREAS NORTH/EAST OF DALLAS/FORT WORTH. BEST HAIL POTENTIAL SEEMS LIKELY TO REMAIN CONFINED TO AREAS WEST OF THE METROPLEX INTO THE EDWARDS PLATEAU...IN CLOSER PROXIMITY STEEPENING LOW-LEVEL LAPSE RATES. ..KERR.. 04/28/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT... 32009985 33419856 34069811 34639740 34709621 34359515 33719492 32009692 31089794 30869953 WWWW From Mcd at goshenarc.org Sat Apr 29 01:44:51 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 21:44:51 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290144 SWOMCD SPC MCD 290144 OKZ000-TXZ000-290315- MESOSCALE DISCUSSION 0686 NWS STORM PREDICTION CENTER NORMAN OK 0844 PM CDT FRI APR 28 2006 AREAS AFFECTED...SOUTHERN OK...NORTH CENTRAL TX CONCERNING...TORNADO WATCH 258... VALID 290144Z - 290315Z ...SEVERE THREAT IS INCREASING ACROSS THE METROPLEX... COMPLEX PATTERN HAS EVOLVED ACROSS NORTH CENTRAL TX INTO THE RED RIVER REGION OF SRN OK THIS EVENING. STRENGTHENING WARM ADVECTION BENEATH LLJ APPEARS TO BE PARTLY RESPONSIBLE FOR EXPANDING SEVERE CLUSTERS ALONG THE RED RIVER...TRAILING SWWD INTO STEPHENS COUNTY TX. ONE LONG LIVED DESTRUCTIVE SUPERCELL OVER GRAYSON COUNTY TX SEEMS TO HAVE BEEN ENHANCED BY STRONG LOW LEVEL SHEAR ALONG RETREATING BOUNDARY THAT IS LOSING IDENTITY OVER NERN TX. RECENT TRENDS SUGGEST AN UPWARD EXPANSION OF ACTIVITY FROM WEST-NORTH OF THE METROPLEX. THIS CONVECTION WILL SPREAD ACROSS THE REMAINDER OF NORTH CENTRAL TX LATER THIS EVENING INTO THE EARLY MORNING HOURS. ADDITIONAL THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG ADVANCING COLD FRONT AS IT SWEEPS SEWD LATER TONIGHT. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...TSA...FWD...OUN... 34199808 34449553 33629538 33399626 32979682 32339750 32339892 WWWW From Mcd at goshenarc.org Sat Apr 29 03:03:59 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Fri, 28 Apr 2006 23:03:59 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290303 SWOMCD SPC MCD 290303 TXZ000-290430- MESOSCALE DISCUSSION 0687 NWS STORM PREDICTION CENTER NORMAN OK 1003 PM CDT FRI APR 28 2006 AREAS AFFECTED...EAST TX CONCERNING...TORNADO WATCH 258...259... VALID 290303Z - 290430Z ...SEVERE THREAT WILL INCREASE EAST OF WATCHES 258/259 ACROSS EAST TX BY THE EARLY MORNING HOURS. TORNADO WATCH WILL BE ISSUED BY MIDNIGHT... COLD FRONT CONTINUES TO SURGE SWD ACROSS THE TX HIGH PLAINS WHILE WARM ADVECTION APPEARS TO BE THE PRIMARY AGENT IN SEVERE THUNDERSTORM CLUSTERS FROM NEAR THE RED RIVER...SWD INTO THE HILL COUNTRY. AS LARGE SCALE FORCING SPREADS ACROSS CNTRL TX CONVECTION SHOULD BEGIN TO DEVELOP NEAR THE ERN EDGE OF TORNADO WATCHES...BENEATH STRONG LLJ. LATEST THINKING IS SEVERE THUNDERSTORM CLUSTERS OVER THE HILL COUNTRY...AND OVER THE DFW METROPLEX WILL BE APPROACHING THE ERN EDGE OF TORNADO WATCHES BY MIDNIGHT. GIVEN THE STRONG LOW LEVEL SHEAR...40KT SFC-1KM/HELICITY...500-700M2/S2...NEW TORNADO WATCH WILL BE ISSUED DOWNSTREAM TO ACCOUNT FOR THIS EVOLUTION. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...SHV...HGX...FWD...EWX... 30039740 33589625 33109433 30049552 WWWW From Mcd at goshenarc.org Sat Apr 29 04:15:08 2006 From: Mcd at goshenarc.org (Mesoscale Convective Discussions) Date: Sat, 29 Apr 2006 00:15:08 -0400 Subject: [MCD] SWOMCD Message-ID: ACUS11 KWNS 290414 SWOMCD SPC MCD 290414 TXZ000-290545- MESOSCALE DISCUSSION 0688 NWS STORM PREDICTION CENTER NORMAN OK 1114 PM CDT FRI APR 28 2006 AREAS AFFECTED...SOUTH CENTRAL TX CONCERNING...TORNADO WATCH 259... VALID 290414Z - 290545Z ...SEVERE THREAT IS INCREASING ACROSS SOUTH CENTRAL TX...WW WILL LIKELY BE ISSUED JUST SOUTH OF WW259... LATEST DIAGNOSTIC DATA SUGGESTS LOW LEVEL CONVERGENCE WILL PROVE SUFFICIENT IN FORCING BOUNDARY LAYER PARCELS TO THEIR LFC ALONG ADVANCING WIND SHIFT. RADAR TRENDS SUPPORT THIS WITH SWWD DEVELOPMENT ALONG PRE-FRONTAL BOUNDARY INTO NERN MEXICO WEST OF DRT. FORECAST SOUNDINGS SUGGEST STRONG CAP JUST SOUTH OF CURRENT WW259 WILL BE REMOVED THROUGH VERTICAL ASCENT/COOLING. DEVELOPING SQUALL LINE WILL LIKELY ADVANCE INTO PORTIONS OF SOUTH CENTRAL TX NOT CURRENTLY COVERED BY TORNADO WATCH. FOR THIS REASON WILL LIKELY ISSUE ANOTHER SMALL WATCH TO ACCOUNT FOR THIS EVOLUTION. ..DARROW.. 04/29/2006 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...EWX... 30230053 30109845 29209826 28679926 29120077 WWWW